Suppose heights, in inches, of orangutans are normally distributed and have a known population standard deviation of3

inches and an unknown population mean. A random sample of25

orangutans is taken and gives a sample mean of60

inches. Find the error bound (EBM) of the confidence interval with a90%

confidence level.

z

0.10

z

0.05

z

0.025

z

0.01

z

0.005

1.282

1.645

1.960

2.326

2.576

Select the correct answer below:

0.769

0.987

1.176

1.218

1.396

1.546