# Question: Again consider the survey of 350 Bank of America customers

Again consider the survey of 350 Bank of America customers discussed in Exercise 7.29, and assume that 48% of Bank of America customers would currently express customer delight. That is, assume p = .48. Find:

a The probability that the sample proportion obtained from the sample of 350 Bank of America customers would be within three percentage points of the population proportion. That is, find P(.45 ≤ p̂ ≤.51).

b The probability that the sample proportion obtained from the sample of 350 Bank of America customers would be within six percentage points of the population proportion. That is, find P(.42 ≤ p̂ ≤.54)

a The probability that the sample proportion obtained from the sample of 350 Bank of America customers would be within three percentage points of the population proportion. That is, find P(.45 ≤ p̂ ≤.51).

b The probability that the sample proportion obtained from the sample of 350 Bank of America customers would be within six percentage points of the population proportion. That is, find P(.42 ≤ p̂ ≤.54)

## Answer to relevant Questions

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