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.

Short Answer

Expert verified

(a) The sample proportion is0.2orless

(b) The observed sample proportion values is 0.2<p^<0.8.

Step by step solution

01

Part (a) Step 1: Given Information 

Given in the question that, the confidence interval is 0.2orlesswe have to 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.

02

Part (a) Step 2: Explanation 

The educated guess is the value that is closest to the midpoint of the probable range of 0.2or less.

As a result, the sample proportion is estimated to be 0.2

03

Part (b) Step 1: Given Information 

Given in the question that, the confidence interval is 0.2orlesswe have to

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.

04

Part (b) Step 2: Explanation 

The higher margin of error is found in the value range of 0.2-0.8. As a result, the sample proportion observed values range from0.2-0.8. that is0.2<p^<0.8

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