A machine cuts plastic into sheets that are 30 feet 360 inch

A machine cuts plastic into sheets that are 30 feet (360 inches) long. Assume that the population of lengths it normally distributed Complete parts (a) and (b) The company wants to estimate the mean length the machine is cutting the plastic within 0 5 inch Determine the minimum sample sire required to construct a 95 % confidence interval for the population mean Assume the population standard deviation is 1.00 inch. Repeat part (a) using an error tolerance of 0 25 inch. Which error tolerance respires a larger sample sire? Explain.

Solution

a.) Margin of error = E = 0.5

sd=1

Z0.025 = 1.96

n= (Z0.025^2 × sd^2)/E^2

= (1.96^2×1)/0.5^2

= 15.36

= 15

b.) E=0.25

n = (1.96^2×1)/0.25^2

= 61.46

= 61

Option A