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Two samples are shown in Table 10.2. Both have normal distributions. The means for the two populations are thought to be the same. Is there a difference in the means? Test at the 5% level of significance.

Short Answer

Expert verified

There isn't enough data to establish that the two populations' means aren't the same.

Step by step solution

01

Given information

Given a sample of two populations and the level of significance, a=5%

02

Explanation

The null hypothesis is:

H0:μa=μbIH0:μa-μb=0

The alternative hypothesis is:

Ha:μaμbIHa:μa-μb0

The significant level,

a=5%a=0.05

We decline to reject the null hypothesis because the p-value is 0.4125, which is significantly greater than0.05. As a result, there is no reason to believe that the mean of the two populations differs.

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Most popular questions from this chapter

Two types of phone operating system are being tested to determine

if there is a difference in the proportions of system failures (crashes). Fifteen out of a random sample of 150 phones with OS1had system failures within the first eight hours of operation. Nine out of another random sample of 150 phones with OS2had system failures within the first eight hours of operation. OS2is believed to be more stable (have fewer crashes) than OS1.

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a.H0:

b. Ha:

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