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2009-06-05 10:24 am
Each day, the United States Customs Service has historically intercepted about $28 million in contraband goods being smuggled into the country, with a standard deviation of $16 million per day. On 64 randomly chosen days in 1986, the US Customs Service intercepted an average of $30.3 million in contraband goods. Does this sample indicate (at a 5 percent level of significance) that the Customs Commissioner should be concerned that smuggling has increased above its historic level?
回答 (2)
2009-06-05 9:19 pm
✔ 最佳答案
by Central Limit Theorm, the value of contraband goods intercepted is in Normal Distribution with mean $28m and standard deviation $16mNow, a sample mean $30.3m with no. of sample = 64
by standard normal distribution
Z = ($30.3 - HK$28) / [$16 / sqrt(64)] = 1.15
Pr (Z > 1.15) = 12.5% > 5%
Hence, we could conclude that the Customs Commissioner should not be concerned that smuggling has increased above its historic level
2009-06-05 13:56:46 補充：
eag583 is late by 33 seconds
Poor!
2009-06-05 9:52 pm
by Central Limit Theorm, the value of contraband goods intercepted is in Normal Distribution with mean $28m and standard deviation $16m
Now, a sample mean $30.3m with no. of sample = 64
by standard normal distribution
Z = ($30.3 - HK$28) / [$16 / sqrt(64)] = 1.15
Pr (Z > 1.15) = 12.5% > 5%.
Now, a sample mean $30.3m with no. of sample = 64
by standard normal distribution
Z = ($30.3 - HK$28) / [$16 / sqrt(64)] = 1.15
Pr (Z > 1.15) = 12.5% > 5%.
參考: yahoo.com
收錄日期: 2021-04-15 21:27:45
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20090605000051KK00151