Ben bowled 154 and 188 in his first two games. what must he bowl in his third game to have an average of at least 170?
ben must bowl at least
in his third game in order to have an average of at
least 170.

To calculate average, you simply add all the data, and divide it by the number of data.
so in this case, let the third game be y.
so,
(154 + 188 + y)/3 = 170
154 + 188 + y = 510
y = 168
so he must bowl at least 168 in his third game

154 + 188 + x /3 = 170
342 + x /3 = 170
342 + x = 510
x = 168

Ben must bowl at least 168 to have an average of at least 170