QN 5Suppose a marketing research company desires to know the

Q.N. 5)Suppose a marketing research company desires to know the mean consumption of milk per week among males over 27. They believe that milk consumption has a mean of 4.2 liters. Assume the variance is known to he 1.69. How large a sample would he required in order to estimate mean weekly consumption of milk by males over 27 at the 99% confidence level with an error of at most 0.06 liters?

Solution

Sample size

For 99%, z=2.576

d=0.06

variance =s²⁼ 1.69

Sample size = (z²*s²)/d²

= (2.576²*1.69)/0.06²

=3115.128

The sample size required= 3116