One sample has a mean of M=4 and a second sample has a mean of M=8. The two samples are combined into a single set of scores.
a. What is the mean for the combined set if both of the original samples have n=7 scores? The mean will be equal to X = (5*6+5*12)/(5+5) = 9
b. What is the mean for the combined set if the first sample has n=3 and the second sample has n=7? The mean of the combined set would be X = (4*6 + 8*12) / (4+8) = 10.
c. What is the mean for the combined set if the first sample has n=7 and the second sample has n=3?