At my son's school a stage was clumsily erected by dad's that are not too aware of weight loads. The stage is very small enough to place a man and a woman (selected from parents of children attending the school) on top sitting down on chairs were some activity is to take place. Now, the mean weight of the men is ? = 185 lbs and the standard deviation is s = 15 lbs, while the mean weight of the women is ? = 155 lbs and a standard deviation of s = 13 lbs. Let the random variable M represent the weight of a man from this school and the random variable W represents the weight of a woman. A man and a woman will be selected at random to perform some skit on the said stage.
a. What is the value of E(W + M)?
b. What is the value of SD(W + M)?