Simplify. 9y+11z+7y−4z what is the answer?

On average, how many more hits will he get when he bats 100 times at home during the day as opposed to 100 times away at night?

Jose is going to use a random number generator 500500 times. each time he uses it, he will get a 1, 2, 3,1,2,3, or 44.

How can you find the mean absolute deviation (mad) for this set of data?