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a. Determine the sample proportion.

b. Decide whether using the one-proportion z-test is appropriate.

c. If appropriate, use the one-proportion z-test to perform the specified hypothesis test.

x=16

n=20

H0:p=0.7

Ha:p≠0.7

a=0.05

Short Answer

Expert verified

(a) The sample proportion is 0.8.

(b) It is appropriate to use the one proportion z-test.

(c) The hypothesis H0is not rejected.

Step by step solution

01

Part(a) Step 1: Given information

The given data is

x=16

n=20

H0:p=0.7

Ha:p≠0.7

a=0.05

02

Part(a) Step 2: Explanation

Write the expression for the sample proportion as

p^=xn

The sample proportion is calculated as

p^=1620

=0.8.

03

Part (b) Step 1: Given information

The given data is

x=16

n=20

H0:p=0.7

Ha:p≠0.7

a=0.05

04

Part (b) Step 2: Explanation

Test the hypothesis as

H0:p=0.7

H0:p≠0.7

Calculate the value ofnp0

np0=(20)(0.7)

=14

Find the value ofn1-p0

n1-p0=(20)(1-0.7)

=20(0.3)

=6.

Both np0and n(1-p0)have a value greater than 5. So, one proportion z- test is appropriate to use. Therefore, it is appropriate to use the one proportion z-test.

05

Part (c) Step 1: Given information

The given data is

x=16

n=20

H0:p=0.7

Ha:p≠0.7

a=0.05

06

Part (c) Step 2: Explanation

Write the expression for zas

z=p^-p0p01-p0n

The value is calculated as

z=0.8-0.70.7(1-0.7)20

=0.10.1025

=0.9759

≈0.98.

And also, α=0.05

For, α=0.025,the critical value from the standard table is

z0.025=±1.96

The test statistic falls in the acceptance region.

So, the hypothesisH0 is not rejected.

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Most popular questions from this chapter

We have given a likely range for the observed value of a sample proportionp^

0.2orless

a. Based on the given range, identify the educated guess that should be used for the observed value of p^to calculate the required sample size for a prescribed confidence level and margin of error.

b. Identify the observed values of the sample proportion that will yield a larger margin of error than the one specified if the educated guess is used for the sample-size computation.

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We have given a likely range for the observed value of a sample proportion p^

0.7orless

a. Based on the given range, identify the educated guess that should be used for the observed value of p^to calculate the required sample size for a prescribed confidence level and margin of error.

b. Identify the observed values of the sample proportion that will yield a larger margin of error than the one specified if the educated guess is used for the sample-size computation.

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