What must be subtracted from -7 to obtain -15

Ben bowled 124 and 188 in his first two games. what must he bowl in his third game to have an average of at least 160?

Idon’t understand this.. will someone ? will mark brainliest along with 20 points.

Which formula finds the probability that a point on the grid below will be in the blue area? p(blue) = total number of squares number of blue squares number of blue squares p(blue) = total number of squares number of blue squares p(blue) = number of white squares