The ratio of Bobby's age to Japheth's age is 8 : 5. Next year, their average age will be 14. How old will Bobby be in 11 years' time?
| |
Bobby |
Japheth |
Total |
| Before |
8 u |
5 u |
26 |
| Change |
+ 1 |
+ 1 |
|
| After |
8 u + 1 |
5 u + 1 |
28 |
Total age of Bobby and Japheth this year
= 8 u + 5 u
= 13 u
Total age of Bobby and Japheth this year
= 2 x 14 - 1 - 1
= 28 - 2
= 26
13 u = 26
1 u = 26 ÷ 13 = 2
Bobby's age in 11 years' time
= 8 u + 11
= 8 x 2 + 11
= 16 + 11
= 27
Answer(s): 27
