A Simple Random Sample of Size 20 Has Mean $\bar { x } = 70.89$

question 59

Multiple Choice

A simple random sample of size 20 has mean $\bar { x } = 70.89$ and standard deviation s = 16.77. The population distribution is unknown. Determine the correct method of finding a 90% confidence Interval for the population mean and compute it.

• A) Cannot compute: the population size is too small.
• B) z-method: (64.72, 77.06)
• C) t-method: (64.41, 77.37)
• D) z-method: (64.41, 77.37)