A realtor wants to know if the houses in two different blocks were built at roughly the same period. She takes a random sample of eight houses from each block and finds their ages from local records. The following table shows the data for each sample (in years).

Block A Block B 47 40 50 33 46 35 61 51 65 44 56 55 55 57 60 45

a) Find the sample mean for each block.

b) Find the estimated difference of the mean ages of the two blocks.

c) Find the sample variances for each block.

d) Find the sample standard deviation for each block.

e) Find the standard error in the difference of the two sample means.