Step-by-step explanation:
In the case of a discrete probability distribution of a random variable X, the mean is equal to the sum over every possible value weighted by the probability of that value; that is, it is computed by taking the product of each possible value x of X and its probability p(x), and then adding all these products together
Answer: 105$
Half the ppl paid 1.50 for programs which is 15 x 1.5 = 22.5
30 ppl bought tickets 30x2.75
Add the totals to get 105
4 * 45 = 180
265 - 180 = 85
85/5 = 17
They sold 17 rolls of patterned wrapping paper.