You can put this solution on YOUR website! The sum is given as 75, so the average of the 6 numbers is 75/6 = 12.5. So the 6 numbers are "centered" at 12.5; that means the numbers are 12 and 13, 11 and 14, and 10 and 15 -- or 10, 11, 12, 13, 14, and 15.