Question

Diastolic blood pressure measurements on American men ages 18-44 years follow approximately a normal curve with μ = 81 mm Hg and σ =11 mm Hg. The distribution for women ages 18-44 is also approximately normal with the same SD but with a lower mean, μ =75 mm Hg. Suppose we are going to measure the diastolic blood pressure of n randomly selected men and n randomly selected women in the age group 18-44 years. Let E be the event that the difference between men and women will be found statistically significant by a t test. How large must n be in order to have Pr[ E] = 0.9? a. if we use a two tailed t test at a = 0.05? b .if we use a two tailed t test at a= 0.01? c. if we use a one tailed t test in the correct direction at a=0.05 ?

Answer 1