The ratio of Xavier's age to Oliver's age is 9 : 5. Next year, their average age will be 15. How old will Xavier be in 5 years' time?
| |
Xavier |
Oliver |
Total |
| Before |
9 u |
5 u |
28 |
| Change |
+ 1 |
+ 1 |
|
| After |
9 u + 1 |
5 u + 1 |
30 |
Total age of Xavier and Oliver this year
= 9 u + 5 u
= 14 u
Total age of Xavier and Oliver this year
= 2 x 15 - 1 - 1
= 30 - 2
= 28
14 u = 28
1 u = 28 ÷ 14 = 2
Xavier's age in 5 years' time
= 9 u + 5
= 9 x 2 + 5
= 18 + 5
= 23
Answer(s): 23
