Question

the set M contains 4positive integers - if the average is 7 what is the highest possible integer in the set M

Answer 1

4 positive integers : x, x + 2, x + 4, x + 6

((x) + (x + 2) + (x + 4) + (x + 6)) / 4 = 7...combine like terms
(4x + 12) / 4 = 7...multiply both sides by 4
4x + 12 = 7 * 4
4x + 12 = 28
4x = 28 - 12
4x = 16
x = 16/4
x = 4

x + 2 = 4 + 2 = 6
x + 4 = 4 + 4 = 8
x + 6 = 4 + 6 = 10

lets check...
(4 + 6 + 8 + 10) / 4 = 7
28/4 = 7
7 = 7 (correct)

the highest possible integer is 10