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《概率论与数理统计》考前练兵
1.[单选题] 设<img id="ODtfisoTEMP20200805030853134.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODtfisoTEMP20200805030853134.png?Expires=1911971333&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=1Jot9BvJEBEOknJ8JtUhiBgTHww%3D" />,其中<img id="ODgqkumTEMP20200805030853457.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODgqkumTEMP20200805030853457.png?Expires=1911971333&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=/Br2zoBzOXedJM2UZKJdvVO54C8%3D" />已知, <img id="ODmgxpyTEMP20200805030854744.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODmgxpyTEMP20200805030854744.png?Expires=1911971334&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=kNOTC8HZHxrjvc9ZgTvLZXYSiwA%3D" />未知,<img id="ODcnrhcTEMP20200805030854915.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODcnrhcTEMP20200805030854915.png?Expires=1911971335&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=ei8bcKBSlRCEgyryChxo1VgLbds%3D" />为其样本,下列各项不<br><br>是统计量的是( )。
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A.<br><img id="ODaexryTEMP20200805030855130.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODaexryTEMP20200805030855130.png?Expires=1911971335&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=KCR9JgSNjXzCL3xga5uH7p/IRyI%3D" />
B.<br><img id="ODbqtrqTEMP20200805030855273.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODbqtrqTEMP20200805030855273.png?Expires=1911971335&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=u9Sc2TYahmDqeOIzbK/NOA5JbjY%3D" />
C.<br> <img id="ODxpzeqTEMP20200805030855434.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODxpzeqTEMP20200805030855434.png?Expires=1911971335&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=muuFlXowhV6QzNKXbsoHZ611cHw%3D" />
D.<br> <img id="ODexwxvTEMP20200805030855611.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODexwxvTEMP20200805030855611.png?Expires=1911971335&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=98pyDzFqCa6hF6%2B//R2ubF%2BNVKY%3D" />
答:——C——
2.[单选题] 某人连续向一目标射击,每次命中目标的概率为3/4,他连续射击直到命中为止,则射击次数为3的概率是( )。
A.<br> <img id="ODunzilTEMP20200805030855750.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODunzilTEMP20200805030855750.png?Expires=1911971335&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=Dj6ZqSEuhaX7KHvnqJkIiSFVSrQ%3D" />
B.<br> <img id="ODlteoqTEMP20200805030855908.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODlteoqTEMP20200805030855908.png?Expires=1911971336&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=6Wy2nZL3wPcfkYduG%2BYLnmB6o4M%3D" />
C.<br><img id="ODlknvvTEMP20200805030856045.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODlknvvTEMP20200805030856045.png?Expires=1911971336&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=DUkFybPyweRmgA2HOLVkFakv2/4%3D" />
D.<br> <img id="ODwppfbTEMP20200805030856196.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODwppfbTEMP20200805030856196.png?Expires=1911971336&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=Jnd3QoO88QgM1iAyU2FygQBLUBc%3D" />
答:——C——
3.[单选题] 设随机变量<img id="ODwqsiiTEMP20200805030856357.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODwqsiiTEMP20200805030856357.png?Expires=1911971336&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=NcolrItofxj1cxp91e4%2B5Omy6jM%3D" />的分布函数为<img id="ODjkwkyTEMP20200805030856603.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODjkwkyTEMP20200805030856603.png?Expires=1911971336&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=WraMGboygTFS5rsqTsrnWHlgdcU%3D" />,则<img id="ODdpxcbTEMP20200805030856780.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODdpxcbTEMP20200805030856780.png?Expires=1911971336&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=6HlNh0oeYuMAK7hGYWS0RETNlp0%3D" />的值为( )。
A.<br> <img id="ODepvmeTEMP20200805030856941.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODepvmeTEMP20200805030856941.png?Expires=1911971337&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=GbYo4VDRLgCGzCOHLu7hkKmPafA%3D" />
B.<br> <img id="ODgrgeuTEMP20200805030857141.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODgrgeuTEMP20200805030857141.png?Expires=1911971337&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=hp2rqNyJjjNpN528aOWT4XEj/pw%3D" />
C.<br> <img id="ODjdrzeTEMP20200805030857282.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODjdrzeTEMP20200805030857282.png?Expires=1911971340&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=Nx3vjVGj1Ka5pk77Jp%2BEDA0lecc%3D" />
D.<br><img id="ODngekmTEMP20200805030900463.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODngekmTEMP20200805030900463.png?Expires=1911971340&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=09LMi80hqqfLAt07GtUGOvC6k68%3D" />
答:——A——
4.[单选题] 设随机变量<img id="ODmzzqoTEMP20200805030900613.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODmzzqoTEMP20200805030900613.png?Expires=1911971340&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=18pOr4//otDoTgTXgRPfQvRm84Y%3D" />,则随<img id="ODncnglTEMP20200805030900766.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODncnglTEMP20200805030900766.png?Expires=1911971340&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=Q3Zd9Ypllrdjyb22VuvVHRU2QIU%3D" />增大,<img id="ODfndmwTEMP20200805030900918.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODfndmwTEMP20200805030900918.png?Expires=1911971341&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=1kISWmcXQuWI6%2Bo/njMQss6kbKo%3D" /> ( )。
A.单调增大
B.单调减小
C.保持不变
D.增减不定
答:————
5.[单选题] 掷一枚质地均匀的骰子，则在出现奇数点的条件下出现3点的概率为（ ）。
A.1/3
B.2/3
C.1/6
D.3/6
答:————
6.[判断题] 如果因素<img id="ODxblaxTEMP20200805030901085.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODxblaxTEMP20200805030901085.png?Expires=1911971341&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=zsQG5yCZRn1I6gCBjuzeBVhF/HA%3D" />的各个水平对总体的影响差不多,则<img id="ODxahwuTEMP20200805030901240.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODxahwuTEMP20200805030901240.png?Expires=1911971341&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=L0vDVBEBGMtWkpv25Gep3RJAv8c%3D" />比较大。 ( )
A.对
B.错
答:————
7.[判断题] 袋中10个球．8红2白，现从袋中任取两次．每次取1球作不放回抽样， 两次都取得红球的概率为23/45。 （ ）
A.对
B.错
答:————
8.[判断题] 变量间的确定性关系是指当一些变量的值确定后另一些变量的值也随之确定的关系。 （ ）
A.对
B.错
答:————
9.[填空题] 10个球中只有一个红球,有放回地抽取,每次取一球,直到第n次才取得k次(k≤n)红球的概率为______##____。
答:————
10.[填空题] 设(<img id="ODgdpjkTEMP20200805030901646.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODgdpjkTEMP20200805030901646.png?Expires=1911971341&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=pNQV/uekS6gmZ40kdMmWwv65y5U%3D" />)的联合分布律如表所示,则(a,b)=______##______时,<img id="ODkrchtTEMP20200805030901806.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODkrchtTEMP20200805030901806.png?Expires=1911971341&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=ewt9DQRrSvZrrF11onq8zj0XfgQ%3D" />与<img id="ODotzkmTEMP20200805030901944.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODotzkmTEMP20200805030901944.png?Expires=1911971342&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=O5kh2w1uf1Gmith5%2BTl%2B9g9E28U%3D" />相互独立。<br><img id="ODemiqjTEMP20200805030902129.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODemiqjTEMP20200805030902129.png?Expires=1911971342&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=u4HmRyR%2BFuaRMjGPnwkuxwrUy7I%3D" />
答:————
11.[填空题] 设<img id="ODgmwfyTEMP20200805030902503.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODgmwfyTEMP20200805030902503.png?Expires=1911971342&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=w4MhmlWWj2fRum7NTGSAVltTZls%3D" /> 为正态总体<img id="ODqkrdbTEMP20200805030902666.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODqkrdbTEMP20200805030902666.png?Expires=1911971342&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=mDxEignz7Y4IA1311DIi7mt6EfI%3D" />的一个样本,则概率<img id="ODciehqTEMP20200805030902897.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODciehqTEMP20200805030902897.png?Expires=1911971343&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=K0y2UZ53x%2BG8fbSdpZZQqhXjm04%3D" />为<span style="text-decoration: underline;">_______</span><span style="text-decoration: underline;">##</span><span style="text-decoration: underline;">_____</span>。
答:————
12.[填空题] 假设随机变量X服从正态分布<img id="ODtzettTEMP20200805030903034.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODtzettTEMP20200805030903034.png?Expires=1911971343&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=wLrxYzqShzvHvEmOK%2BiGxZxOlCk%3D" />,<img id="ODjkbwzTEMP20200805030903229.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODjkbwzTEMP20200805030903229.png?Expires=1911971343&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=ML1I/2WY7oT7/f6e21Xr52RNzoQ%3D" />是来自X的样本,<img id="ODamfmnTEMP20200805030903399.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODamfmnTEMP20200805030903399.png?Expires=1911971343&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=yrtZGIMikpaA4aKcDoKUMN4if38%3D" />为样本均值,已知<img id="ODvsajuTEMP20200805030903573.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODvsajuTEMP20200805030903573.png?Expires=1911971343&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=nrh1Knou98nLRwJXmkeJMU6g1vY%3D" />,则<img id="ODnoglcTEMP20200805030903790.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODnoglcTEMP20200805030903790.png?Expires=1911971343&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=rMomJgR9xEyZ7mCyU2RLhnKHFZA%3D" /><span style="text-decoration: underline;">______</span><span style="text-decoration: underline;">##</span><span style="text-decoration: underline;">_____</span>。
答:————
13.[填空题] <span style="text-decoration: underline;">设(</span><img id="ODsuplqTEMP20200805030903976.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODsuplqTEMP20200805030903976.png?Expires=1911971344&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=0yhwh3cIlUCS3z4hjwPV4m45vs8%3D" /><span style="text-decoration: underline;">)的</span><span style="text-decoration: underline;">联合分布律如表</span><span style="text-decoration: underline;">所示,则(</span><span style="text-decoration: underline;">p,q</span><span style="text-decoration: underline;">)</span><span style="text-decoration: underline;">=_____</span><span style="text-decoration: underline;">##</span><span style="text-decoration: underline;">_______</span><span style="text-decoration: underline;">时,</span><img id="ODkgvvzTEMP20200805030904258.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODkgvvzTEMP20200805030904258.png?Expires=1911971344&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=EEuH1QAKvpSkCW/ESXSwGMzgjEs%3D" /><span style="text-decoration: underline;">与</span><img id="ODetvmwTEMP20200805030904455.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODetvmwTEMP20200805030904455.png?Expires=1911971344&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=CcJq%2Bsgr0taG3PEmZlxvM2Wg6Oo%3D" /><span style="text-decoration: underline;">相互独立。</span><br><img id="ODadoefTEMP20200805030904636.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODadoefTEMP20200805030904636.png?Expires=1911971344&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=grJqJ1HJoHTDj7fCv1lkOaj0xYA%3D" />
答:————
14.[填空题] 若随机变量<img id="ODnhqxmTEMP20200805030904982.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODnhqxmTEMP20200805030904982.png?Expires=1911971345&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=7ue9OM3UmhC8Gi1g1rd0P3WNwRw%3D" />的期望<img id="ODuhhahTEMP20200805030905171.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODuhhahTEMP20200805030905171.png?Expires=1911971347&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=r%2BTnQrRdm7FUTn4soHjXSe5LjI4%3D" />存在,则<img id="ODsmiodTEMP20200805030907224.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODsmiodTEMP20200805030907224.png?Expires=1911971347&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=CbfFHVCGatCsPRQHNsmDooicf2s%3D" /><span style="text-decoration: underline;">______</span><span style="text-decoration: underline;">##</span><span style="text-decoration: underline;">______</span>。
答:————
15.[填空题] 对于两个正态总体<img id="ODoyqhtTEMP20200805030907685.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODoyqhtTEMP20200805030907685.png?Expires=1911971347&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=1g%2BwxA62wQp3BHMgGUn0nt1dTvI%3D" />与<img id="ODiuidcTEMP20200805030907835.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODiuidcTEMP20200805030907835.png?Expires=1911971347&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=8gfGSO3P3zHzc5v/zKXe%2B1fP4F4%3D" />,则假设<img id="ODsscnzTEMP20200805030908006.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODsscnzTEMP20200805030908006.png?Expires=1911971348&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=ulfCSS2UgKC5EMRg85PevcZLLCA%3D" />的<img id="ODmlmexTEMP20200805030908222.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODmlmexTEMP20200805030908222.png?Expires=1911971348&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=j2mr0OcttpTQwmpzP%2B7DlinPVCE%3D" />检验使用的统计量<img id="ODyixjuTEMP20200805030908416.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODyixjuTEMP20200805030908416.png?Expires=1911971348&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=9HB9/us9BLnu57R55RiEOy5gyv0%3D" />,当第1个样本容量<img id="ODptnqrTEMP20200805030908582.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODptnqrTEMP20200805030908582.png?Expires=1911971348&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=Y1ZoTtz8ZV%2BwGllIgYbxw4J6kcE%3D" />,第2个样本容量<img id="ODuchcuTEMP20200805030908716.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODuchcuTEMP20200805030908716.png?Expires=1911971348&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=yDHbN0LzkRKfNg3l49VX7fg/1nA%3D" />时,在显著水平<img id="ODlqhfkTEMP20200805030908898.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODlqhfkTEMP20200805030908898.png?Expires=1911971349&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=kyCEQhLoY3jN/dvQL2oPZWfYkco%3D" />下,其拒绝域<img id="ODnboxjTEMP20200805030909048.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODnboxjTEMP20200805030909048.png?Expires=1911971349&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=WXUbjCCqWm5Xh0N5FGovb1Z4VrM%3D" />为<span style="text-decoration: underline;">_____</span><span style="text-decoration: underline;">##</span><span style="text-decoration: underline;">______</span>。
答:————
16.[填空题] 设总体<img id="ODyhaphTEMP20200805030909448.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODyhaphTEMP20200805030909448.png?Expires=1911971349&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=ptxI9aFahAk074mM%2BIsfDl9WQoM%3D" />,<img id="ODqirtzTEMP20200805030909613.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODqirtzTEMP20200805030909613.png?Expires=1911971349&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=gZ9mefywxqEFdf2wdu6b9McFU5c%3D" />已知,<img id="ODdwmtiTEMP20200805030909770.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODdwmtiTEMP20200805030909770.png?Expires=1911971349&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=2OsLjXqaSTjt9jYVU27fSyXtH6E%3D" />为未知参数,<img id="ODfceeoTEMP20200805030909908.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODfceeoTEMP20200805030909908.png?Expires=1911971350&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=XoR4fkm6Ny%2BuCkB/tBSU9dUmYyU%3D" />为样本,又<img id="ODprlkmTEMP20200805030910061.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODprlkmTEMP20200805030910061.png?Expires=1911971350&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=h3G18CwQfe9dPv%2BPMqO9vyhSvRM%3D" />表示标准正态分布<img id="ODdesalTEMP20200805030910231.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODdesalTEMP20200805030910231.png?Expires=1911971350&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=Valq4SLUDOa2MkBYa1sVL50xPI4%3D" />的分布函数,已知的置<img id="ODnkrwcTEMP20200805030910410.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODnkrwcTEMP20200805030910410.png?Expires=1911971350&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=fPfw%2B5/1tx2PVGWRxZU7nss%2B9LQ%3D" />在95%置信水平下的置信区间的zα/2为<span style="text-decoration: underline;"> _</span><span style="text-decoration: underline;">##</span><span style="text-decoration: underline;"> </span>
答:————
17.[填空题] 每次试验失败的概率为p(0____##______。
答:————
18.[填空题] 二维离散型随机变量<img id="ODlkhtbTEMP20200805030910704.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODlkhtbTEMP20200805030910704.png?Expires=1911971350&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=gSwpO/ZDdYnKGe/EKwK4IRPCiYg%3D" />的分布律为:<br><img id="ODnvnzbTEMP20200805030910888.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODnvnzbTEMP20200805030910888.png?Expires=1911971351&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=a5wkXFk0iY30Czt1DN2YgTh0h5Y%3D" />则<img id="ODhuexpTEMP20200805030911047.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODhuexpTEMP20200805030911047.png?Expires=1911971351&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=KNqgdxVZlzwgMVBz2%2BX32tsMs0o%3D" />=<span style="text-decoration: underline;"> _</span><span style="text-decoration: underline;">##</span><span style="text-decoration: underline;">_ </span>。
答:————
19.[填空题] 设随机变量(X,Y)的概率密度为f(x,y)=<img id="ODfxpyaTEMP20200805030911226.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODfxpyaTEMP20200805030911226.png?Expires=1911971351&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=RzP883dAO1OjR1HjFTl8lEuDUbI%3D" />,则X的边缘概率密度<img id="ODxqhkyTEMP20200805030911387.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODxqhkyTEMP20200805030911387.png?Expires=1911971351&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=SUNX7bwsyTPd3GQAUdAoe8C9FYU%3D" /><span style="text-decoration: underline;">____</span><span style="text-decoration: underline;">##</span><span style="text-decoration: underline;">_____</span>。
答:————
20.[填空题] 设<img id="ODtcmtcTEMP20200805030911737.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODtcmtcTEMP20200805030911737.png?Expires=1911971351&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=Y/YkiZuW2BVZJ%2BnfqETZMgoqZOc%3D" />和<img id="ODaowpcTEMP20200805030911916.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODaowpcTEMP20200805030911916.png?Expires=1911971352&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=fdJqYC/2nmMOvnPa6EgkfeSqbRU%3D" />独立,且X,Y均服从(0,5)上的均匀分布,则X,Y的概率密度函数是<span style="text-decoration: underline;">____</span><span style="text-decoration: underline;">##</span><span style="text-decoration: underline;">______</span>。
答:————
21.[填空题] 设随机变量<img id="ODgnixlTEMP20200805030912223.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODgnixlTEMP20200805030912223.png?Expires=1911971352&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=7nWxByP1pFa2wWUIdtb%2Bj6fcvAU%3D" />,则<img id="ODizxwnTEMP20200805030912393.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODizxwnTEMP20200805030912393.png?Expires=1911971352&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=z3vBVWTX4PrSkZ6NdS4Q4BwT9/w%3D" /><span style="text-decoration: underline;">_____</span><span style="text-decoration: underline;">##</span><span style="text-decoration: underline;">_______</span>。
答:————
22.[填空题] 设正态总体<img id="ODpwyffTEMP20200805030912543.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODpwyffTEMP20200805030912543.png?Expires=1911971352&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=XcmvQVO680vcuSSQz60n04/EzPM%3D" />,<img id="ODhkeiaTEMP20200805030912720.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODhkeiaTEMP20200805030912720.png?Expires=1911971352&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=IlH1mNxku4XDd4Urs9R8Ca9QgQA%3D" />~<span style="text-decoration: underline;">______</span><span style="text-decoration: underline;">##</span><span style="text-decoration: underline;">______</span>。
答:————
23.[填空题] 在区间估计时，对于同一样本，若置信度设置越高，则置信区间的宽度就##。
答:————
24.[问答题] 某人射击中靶的概率为0.75.若射击直到中靶为止,求射击次数为3的概率。
答:————
25.[问答题] 设随机变量<img id="ODjhzyxTEMP20200805030913923.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODjhzyxTEMP20200805030913923.png?Expires=1911971354&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=8UNNdZk46KCgp043dCuPSf9Cmxk%3D" />的概率密度为<img id="ODrvoaoTEMP20200805030914101.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODrvoaoTEMP20200805030914101.png?Expires=1911971354&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=v/hY3ROdmPDg/4hUjPS92lVJoy4%3D" /> <img id="ODinfnuTEMP20200805030914296.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODinfnuTEMP20200805030914296.png?Expires=1911971354&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=6dny/2K5sw/tgN08WgflGj1fFTE%3D" />且<img id="ODsweecTEMP20200805030914466.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODsweecTEMP20200805030914466.png?Expires=1911971354&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=MQk6jwojZbsOC6yWvno7o5qeNK0%3D" />,则K和b分别为多少?
答:————
26.[问答题] 已知<img id="ODnfkllTEMP20200805030914963.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODnfkllTEMP20200805030914963.png?Expires=1911971355&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=NjfS/i3ZJDZ7avS77nHSEvxvo20%3D" />协方差矩阵为<img id="ODetxlcTEMP20200805030915159.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODetxlcTEMP20200805030915159.png?Expires=1911971355&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=grO9%2BoSvS9e1Jpvd0Y9semJx5g8%3D" />,求<img id="ODdxkpxTEMP20200805030915390.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODdxkpxTEMP20200805030915390.png?Expires=1911971355&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=P%2BD8bWNGp8zADl230lLx1EA3JsE%3D" />与<img id="ODqkzrtTEMP20200805030915547.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODqkzrtTEMP20200805030915547.png?Expires=1911971355&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=yqlIGuAgqs2WvziMkNILBDwgSEE%3D" />的相关系数。
答:————
27.[问答题] 巴斯卡尔认识两个赌徒,这两个赌徒向他提出了一个问题。他们说,他们俩下赌金之后,约定谁先赢满5局,谁就获得全部赌金。赌了半天,A赢了4局,B赢了3局,时间很晚了,他们都不想再赌下去了。那么,这个钱应该怎么分?
答:————
28.[问答题] 设连续型随机变量<img id="ODskfhwTEMP20200805030916168.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODskfhwTEMP20200805030916168.png?Expires=1911971356&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=8BbAYSdkIqH50L1ooj3J4ORepzg%3D" />的分布函数为<img id="ODfluxrTEMP20200805030916362.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODfluxrTEMP20200805030916362.png?Expires=1911971356&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=w/jendcUb/QmPjVKnSHx3KOM37o%3D" />,求<img id="ODkmihnTEMP20200805030916802.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODkmihnTEMP20200805030916802.png?Expires=1911971356&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=nJiM6Ddl0lf7F0ppVcppGRAw1Ao%3D" />的期望与方差的值。
答:————
29.[问答题] 设有来自三个地区的各10名,15名,和25名考生的报名表,其中女生的报名表分别为3份,7份和5份,随机地取一个地区的报名表,从中先后抽取两份。求先抽到的一份是女生表的概率。
答:————
30.[问答题] 一电子仪器由两个部件构成,以X和Y分别表示两部件的寿命(单位:千小时),已知X,Y的联合分布函数为<br><img id="ODktgwxTEMP20200805030919049.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODktgwxTEMP20200805030919049.png?Expires=1911971359&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=%2BBEThwnbcWsUO%2B55E0yMFvYSEHE%3D" /><br>求两个部件的寿命都超过100小时的概率。
答:————
31.[问答题] 某单位有三辆汽车参加某种事故保险,单位年初向保险公司缴纳每辆900元的保险金,对在一年内发生此种事故的每辆汽车,单位可获9000元的赔偿(假设每辆车最多只赔偿一次),设这三辆车在一年内发生此种事故的概率分别为1/9,1/10,1/11,且各车是否发生事故相互独立,求一年内该单位在此保险中获赔金额<img id="ODnonelTEMP20200805030919761.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODnonelTEMP20200805030919761.png?Expires=1911971359&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=VRVMnCM462FFJrPDWxooqJH6ejw%3D" />的分布列与期望。。
答:————
32.[问答题] 一次投掷两颗骰子,求出现的点数之和为奇数的概率。
答:————
33.[问答题] 某种型号器件的寿命<img id="ODgrbjuTEMP20200805030922045.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODgrbjuTEMP20200805030922045.png?Expires=1911971362&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=hY1P1E8WdwBBecDduJ3UGEReDV8%3D" />(以小时计)具有以下的概率密度:<br><img id="ODgmsqbTEMP20200805030922543.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODgmsqbTEMP20200805030922543.png?Expires=1911971362&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=1xjZkY/ST4Rcq0XStYxRNRB9XHA%3D" /><br>现有一大批此种器件(设各器件损坏与否相互独立),任取5只,问其中至少有2只器件的寿命大于1500小时的概率是多少?。
答:————
34.[问答题] 设随机变量<img id="ODxhrbuTEMP20200805030923283.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODxhrbuTEMP20200805030923283.png?Expires=1911971363&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=3X1yWn4s5xGS4XhGFLm0XXbvmIU%3D" />的概率密度为<br><img id="ODkbydhTEMP20200805030923461.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODkbydhTEMP20200805030923461.png?Expires=1911971363&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=khH8tn/GLuYfA6B1NE6GiEBQalw%3D" /><br>问<img id="ODxrudnTEMP20200805030923674.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODxrudnTEMP20200805030923674.png?Expires=1911971363&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=yIvE2n3PPMwva7iBvK6dl/3Y1TU%3D" />和<img id="ODljyzhTEMP20200805030923852.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODljyzhTEMP20200805030923852.png?Expires=1911971363&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=TmxrxexJFjyv/F9FuWDxPHMeBeo%3D" />是否相互独立,请说明理由.<br>求<img id="ODdlfhkTEMP20200805030924034.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODdlfhkTEMP20200805030924034.png?Expires=1911971364&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=f3uq1egN8FxY7rgY2y2JuCXJMX4%3D" />的概率密度<img id="ODgrkylTEMP20200805030924206.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODgrkylTEMP20200805030924206.png?Expires=1911971364&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=gEzwrXXFOXoJGZN//xSMRc3jBcw%3D" />.
答:————
35.[问答题] 一部件包括10部分,每部分的长度是一个随机变量,它们相互独立,且服从同一分布,其数学期望为2mm,均方差为0.05mm.规定总长度为(20±0.1)mm时产品合格,试求产品合格的概率。
答:————
36.[问答题] 对某一距离进行5次测量,结果如下:<br>_______________ <img id="ODxmccvTEMP20200805030929172.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODxmccvTEMP20200805030929172.png?Expires=1911971369&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=2Po/HSUly0JlCukmI9uXi4tCD6I%3D" />(米).<br>已知测量结果服从<img id="ODekifvTEMP20200805030929312.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODekifvTEMP20200805030929312.png?Expires=1911971369&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=jsIRhrR7ZA2ClAb3uwNkZjAT/3k%3D" />,求参数<img id="ODbergnTEMP20200805030929508.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODbergnTEMP20200805030929508.png?Expires=1911971369&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=EET7cgYO6mes/9p3mzhpg%2Bk32fM%3D" />和<img id="ODxltmnTEMP20200805030929649.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODxltmnTEMP20200805030929649.png?Expires=1911971369&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=cSgo1PoonBe7n%2Ba2cG5mnxciSCs%3D" />的矩估计.
答:————
37.[问答题] 设<img id="ODmhacfTEMP20200805030930956.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODmhacfTEMP20200805030930956.png?Expires=1911971371&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=uWZzneF3uvdrICc4kXeVfZdaUlo%3D" />是来自对数级数分布<br><img id="ODasvgfTEMP20200805030931091.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODasvgfTEMP20200805030931091.png?Expires=1911971371&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=zoiJgxfNby2W%2BMwyTXiWrpIu8Jg%3D" /><br>的一个样本,求<img id="ODiuoewTEMP20200805030931261.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODiuoewTEMP20200805030931261.png?Expires=1911971371&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=jb5lpBY82XG/UI1SeqiN3ssAwWA%3D" />的矩估计.。
答:————
38.[问答题] 设总体<img id="ODtgrvjTEMP20200805030932610.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODtgrvjTEMP20200805030932610.png?Expires=1911971372&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=FFFzrQPhhtDU4oeFnC51e4UykSE%3D" />服从参数为<img id="ODwdragTEMP20200805030932739.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODwdragTEMP20200805030932739.png?Expires=1911971372&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=DUwU8W0dMZ6xFH6N9rk%2BdHBhag0%3D" />和<img id="ODgcpqzTEMP20200805030932880.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODgcpqzTEMP20200805030932880.png?Expires=1911971372&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=7tj5NECt1PZxubboB2CXgW/TRm0%3D" />的二项分布,<img id="ODhmqvdTEMP20200805030933018.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODhmqvdTEMP20200805030933018.png?Expires=1911971373&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=6nNQJstHeZWyE0FZibT8ui4stts%3D" />为取自<img id="ODnaficTEMP20200805030933182.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODnaficTEMP20200805030933182.png?Expires=1911971373&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=i0LVEthCnjO7xxDbSzGzy0zJi40%3D" />的样本,试求参数<img id="ODhtlnlTEMP20200805030933322.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODhtlnlTEMP20200805030933322.png?Expires=1911971373&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=agPVZC4xMNQT/NxuX6OWZ%2B3TO9o%3D" />和<img id="ODzktshTEMP20200805030933467.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODzktshTEMP20200805030933467.png?Expires=1911971373&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=xzEwVEs035u5nB4/t2%2Bp/OO7dJY%3D" />的矩估计。
答:————
39.[问答题] 某种零件的尺寸方差为<img id="ODjrtdbTEMP20200805030935531.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODjrtdbTEMP20200805030935531.png?Expires=1911971375&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=7gVjyEiYwgQw2abhhhgsVFHVwGs%3D" />,对一批这类零件检查6件得尺寸数据(毫米):32.56, 29.66, 31.64, 30.00, 21.87, 31.03。设零件尺寸服从正态分布,问这批零件的平均尺寸能否认为是32.50毫米(<img id="ODlnkwnTEMP20200805030935680.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODlnkwnTEMP20200805030935680.png?Expires=1911971375&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=xil5xZDYsoIlGGlsdJuSUKYabXs%3D" />).
答:————
40.[问答题] 设某产品的指标服从正态分布,它的标准差为<img id="ODnobuaTEMP20200805030937311.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODnobuaTEMP20200805030937311.png?Expires=1911971377&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=LvJjDJxCM7dybBcit5ki2pb5r1s%3D" />,今抽了一个容量为26的样本,计算平均值1580,问在显著性水平<img id="ODufbesTEMP20200805030937495.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODufbesTEMP20200805030937495.png?Expires=1911971377&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=nQtebz%2B43AH1h13ObMCjrR6ZAHw%3D" />下,能否认为这批产品的指标的期望值<img id="ODjngxjTEMP20200805030937668.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODjngxjTEMP20200805030937668.png?Expires=1911971377&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=snVmjtc7qoJIDWahWsNo4szqRLE%3D" />不低于1600。
答:————
41.[问答题] 一种元件,要求其使用寿命不低于1000小时,现在从这批元件中任取25件,测得其寿命平均值为950小时,已知该元件寿命服从标准差为<img id="ODucvscTEMP20200805030939374.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODucvscTEMP20200805030939374.png?Expires=1911971379&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=Ew36B51yCx9Jo9Ahv3tiewUy7lE%3D" />小时的正态分布,问这批元件是否合格?(<img id="ODzzwrgTEMP20200805030939555.png" src="http://aseancdn.open.com.cn/zyglpt/OD/TEMP/2020/0805/ODzzwrgTEMP20200805030939555.png?Expires=1911971379&OSSAccessKeyId=gbI8DRLk7JJhLbEw&Signature=iatvvIvja7hLeer4zyIWqbFeOP8%3D" />)
答:————
42.[问答题] 一次投掷两颗骰子,求出现的点数之和为奇数的概率。
答:————
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