Question

The sum of the ages of Mark, Tim and Jane is 39. In 5 years, the ratio of Mark's

5 age to
Tim's age to Jane's age will be 10:9:8. How old is Mark now?
A.
В.
C.
D.
15
14
13
20​

Answer 1

A. 15

Explanation:

10 : 9 : 8

Mark: 10x

Tim: 9x

Jane: 8x

(10x - 5) + (9x - 5) + (8x - 5) = 39

10x - 5 + 9x - 5 + 8x - 5 = 39

27x - 5 - 5 - 5 = 39

27x - 15 = 39

27x - 15 + 15 = 39 + 15

27x = 54

27x ÷ 27 = 54 ÷ 27

x = 2

Mark: 10x - 5

10x - 5

10(2) - 5

20 - 5

15