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【四技應用統計學】假設檢定的問題2

四題原文題5. A manufacturer states that the average lifetime of its television sets is more than 84 months. The standard deviation of the population is 【10】months. One hundred sets are randomly selected and tested.The average lifetime of the sample is 【85.1】 months

and find the P-value. On the basis of the P-value

should the null hypothesis be rejected at 阿法 = 0.01?6. Ten years ago

the average acreage of farms in a certain geographic region was 【65 】acres. The standard deviation ofthe population was 【7 】acres. A recent study consisting of 【22】 farms showed that the average was 【63.2】 acres per farm. Test the claim

at 阿法 = 【0.10】

that the average has not changed by finding the P-value for the test. Assume that 阿法 has not changed and the variable is normally distributed.7.The average undergraduate cost for tuition

fees

and room and board for two-year institutions last year was $【13

252】.The following year

a radom sample of 【20】 two-year institutions had a mean of $【15

560】 and a standard deviation of $【3

500】. Is there sufficient evidence at the 阿法 =【 0.01】 level to conclude that the mean cost has increased?8.A new laboratory technician read a report that the average number of students using the computer laboratory per hour was 【16】. To test this hypothesis

he selected a day at random and kept track of the number of students who used the lab over an 【8-hour period】 . The results were as follows:【20】 【24】 【18】 【16】 【16 】【19】 【21】 【23】At 阿法= 【0.05

test the claim that the average is actually【 16】.Use the P-value method.
5.H0: