Question: Random sampling from two normal populations produced the following results:
x1 = 412 s1 = 128 n1 = 150
x2 = 405 s2 = 54 n2 = 150
a) Can we infer at the 5% significance level that μ1 is greater than μ2?
b) Repeat Part a decreasing the standard deviations to s1 = 31 and s2 = 16.
c) Describe what happens when the sample standard deviations get smaller.
d) Repeat Part a with samples of size 20
e) Discuss the effects of decreasing the sample size
f) Repeat Part a changing the mean of sample 1 to x1‾ = 409
g) Discuss the effect of decreasing x1‾ = 1.