Question

The lowest and highest observations in a population are 13 and 45, respectively. What is the minimum sample size n required to estimate μ with 90% confidence if the desired margin of error is E = 2.5? What happens to n if you decide to estimate μ with 99% confidence? Use Table 1. (Round intermediate calculations to 4 decimal places and "z-value" to 3 decimal places. Round up your answers to the nearest whole number.)

Confidence Level

90% =

99% =

In the planning stage, a sample proportion is estimated as pˆp^ = 56/70 = 0.80. Use this information to compute the minimum sample size n required to estimate p with 95% confidence if the desired margin of error E = 0.09. What happens to n if you decide to estimate p with 90% confidence? Use Table 1. (Round intermediate calculations to 4 decimal places and "z-value" to 3 decimal places. Round up your answers to the nearest whole number.)

Confidence Level	n
95%
90%

Answer 1