If 20m − n = p, then which of the following represents the average (arithmetic mean) of m, n, and p, in terms of m?\nOptions:\n(A) 2m −1\n(B) 4m\n(C) 6m\n(D) 7m\n(E) 6m/5 Let's think first. Stream of consciousness:
User
20m - n = p\nAdd n to both sides:\n20m = n + p\nAdd m to both sides:\n21m = n + p + m\nNow, divide both sides by 3\n7m = (n + p + m)/3 = the average of n, p, and m
So, the answer is (D).
Assistant