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Chapter 10: Q 4. (page 639)

Literacy Refer to Exercise 2.

a. Find the probability that the proportion of graduates who pass the test is at most 0.20higher than the proportion of dropouts who pass, assuming that the researcher’s report is correct.

b. Suppose that the difference (Graduate – Dropout) in the sample proportions who pass the test is exactly 0.20. Based on your result in part (a), would this give you reason to doubt the researcher’s claim? Explain your reasoning.

Short Answer

Expert verified

a. P(z<-2.61)=0.00453

b. Due to small value of probability, there is reason to doubt company's claim.

Step by step solution

01

Given Information

It is given that μ=0.40

σ=0.07745

p^G-p^D=0.20

02

Calculation of Probability

Using z=x-μσ

=0.20-0.400.07745≈-2.61

Hence, P(z<-2.61)=0.00453

=0.45%

03

Reason to Doubt Company's Claim

As we have calculated P(z<-2.61)=0.00453. Is is very small.

There is reason to doubt company's claim.

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Most popular questions from this chapter

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who will develop AIDS in a given period of time?

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(c) It is multiplied by 4.

(d) It is divided by 2.

(e) It is divided by 4.

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c. Given that the true mean difference (Variety A – Variety B) in yield for these two varieties of tomato plants is0, the probability of getting a sample mean difference of0.34or greater is0.227.

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e. Given that the true mean difference (Variety A – Variety B) in yield for these two varieties of tomato plants is not 0, the probability of getting a sample mean difference greater than or equal to 0.34or less than or equal to −0.34is0.227.

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c. What conclusion would you make?
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