The ratio of Simon's age to Gabriel's age is 3 : 1. Next year, their average age will be 11. How old will Simon be in 10 years' time?
| |
Simon |
Gabriel |
Total |
| Before |
3 u |
1 u |
20 |
| Change |
+ 1 |
+ 1 |
|
| After |
3 u + 1 |
1 u + 1 |
22 |
Total age of Simon and Gabriel this year
= 3 u + 1 u
= 4 u
Total age of Simon and Gabriel this year
= 2 x 11 - 1 - 1
= 22 - 2
= 20
4 u = 20
1 u = 20 ÷ 4 = 5
Simon's age in 10 years' time
= 3 u + 10
= 3 x 5 + 10
= 15 + 10
= 25
Answer(s): 25
