Question

let x and y be positive integers.how much greater is the average of 9x,24y,and 48 than the average of 6x,18y,and 12? A) x+2y+12 B)x+2y+24 C) 2x+y+36 D) none of these

Answer 1

the average of  the first expression is found by adding and divding by 3
= (9x + 24y + 48) / 3 =  3x + 8y + 16

also average for second one =  (6x + 18y + 12) / 3 =  2x + 6y + 4

so answer is  3x + 8y + 16 - ( 2x + 6y + 4)  =  x + 2y + 12


Option A