Yen will be 16 years old in 8 years' time. Now, Marion's age is 12 of Yen's age. What was Marion's age when she was 2 years less than 90% of Yen's age?
| |
Marion |
Yen |
Difference |
| Before |
9 p - 2 |
10 p |
1 p + 2 |
| Change 1 |
+ ? |
+ ? |
|
| After 1 (Now) |
1 u |
2 u |
1 u |
| Change 2 |
+ 8 |
+ 8 |
|
| After |
1 u + 8 |
16 |
|
Yen's age in 8 years' time = 2 u + 8
2 u + 8 = 16
2 u = 16 - 8
2 u = 8
1 u = 8 ÷ 2 = 4
Difference between Yen's age and Marion's age
= 1 u
= 4
90% =
90100 =
910 Difference in Yen's age and Marion's age at first
= 10 p - (9 p - 2)
= 1 p + 2
The difference in age between Yen and Marion remains unchanged.
1 p + 2 = 4
1 p = 4 - 2 = 2
Marion's age when she was 2 years less than 90% of Yen's age
= 9 p - 2
= 9 x 2 - 2
= 18 - 2
= 16
Answer(s): 16
