Answer:
the number is 65
Step-by-step explanation:
the same number is added. so let the number be 'x'
the equation can hence be written as:
15 + x / 31 + x = 5 / 6
(now cross multiply)
6 (15 + x) = 5 (31 + x)
90 + 6x = 155 + 5x
6x - 5x = 155 - 90
x = 65
