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In each of the following settings, check whether the conditions for calculating a confidence interval for the population proportion p are met.

1. An AP Statistics class at a large high school conducts a survey. They ask the first 100 students to arrive at school one morning whether or not they slept at least 8 hours the night before. Only 17 students say "Yes."

2. A quality control inspector takes a random sample of 25 bags of potato chips from the thousands of bags filled in an hour. Of the bags selected, 3 had too much salt.

Short Answer

Expert verified

No, the condition of normality is not satisfied.

Step by step solution

01

GIven Information

Number of success (x) =3

Number of trials (n)=25

02

Explanation

One of the required conditions to construct the confidence interval for proportion is that np^>10

Here,

25(0.12)=3<10

Thus, the conditional normality is not satisfied here.

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Most popular questions from this chapter

The Gallup Poll interviews 1600people. Of these, 18%say that they jog regularly. The news report adds: "The poll had a margin of error of plus or minus three percentage points at a 95%confidence level." You can safely conclude that

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Interpret the interval in context. Putting It All Together

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