The ratio of Jeremy's age to Andy's age is 5 : 3. Last year, their average age was 19. How old will Andy be in 10 years' time?
|
Jeremy |
Andy |
Total |
Before |
5 u - 1 |
3 u - 1 |
38 |
Change |
+ 1 |
+ 1 |
|
After |
5 u |
3 u |
40 |
Total age of Jeremy and Andy this year
= 5 u + 3 u
= 8 u
Total age of Jeremy and Andy this year
= 2 x 19 + 1 + 1
= 38 + 2
= 40
8 u = 40
1 u = 40 ÷ 8 = 5
Andy's age in 10 years' time
= 3 u + 10
= 3 x 5 + 10
= 15 + 10
= 25
Answer(s): 25