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Chapter 8: Q6 (page 371)

Identifying H0and H1. In Exercises 5–8, do the following:

a. Express the original claim in symbolic form.

b. Identify the null and alternative hypotheses.

Cell Phone Claim: Fewer than 95% of adults have a cell phone. In a Marist poll of 1128 adults, 87% said that they have a cell phone.

Short Answer

Expert verified

a. The original claim in symbolic form is written in the following manner:

p<0.95

b. The null hypothesis and the alternative hypothesis are as follows:

H0:p=0.95

H1:p<0.95

Step by step solution

01

Given information

Out of 1128 adults, 87% said they have a cell phone.

02

Original claim

a.

It is claimed that less than 95% of adults have a cell phone;this suggests that the original claim should be that the proportion of adults who have a cell phone is less than 95% or 0.95.

Symbolically, the claim would be p<0.95, where p is the proportion of adults who have a cell phone.

03

Hypotheses

b.

Null hypothesis: The proportion of adults who have a cell phone is equal to 0.95.

H0:p=0.95

Alternative hypothesis: The proportion of adults who have a cell phone is less than 0.95.

H1:p<0.95

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