Ivory will be 31 years old in 13 years' time. Now, Jean's age is 12 of Ivory's age. What was Jean's age when she was 5 years less than 75% of Ivory's age?
| |
Jean |
Ivory |
Difference |
| Before |
3 p - 5 |
4 p |
1 p + 5 |
| Change 1 |
+ ? |
+ ? |
|
| After 1 (Now) |
1 u |
2 u |
1 u |
| Change 2 |
+ 13 |
+ 13 |
|
| After |
1 u + 13 |
31 |
|
Ivory's age in 13 years' time = 2 u + 13
2 u + 13 = 31
2 u = 31 - 13
2 u = 18
1 u = 18 ÷ 2 = 9
Difference between Ivory's age and Jean's age
= 1 u
= 9
75% =
75100 =
34 Difference in Ivory's age and Jean's age at first
= 4 p - (3 p - 5)
= 1 p + 5
The difference in age between Ivory and Jean remains unchanged.
1 p + 5 = 9
1 p = 9 - 5 = 4
Jean's age when she was 5 years less than 75% of Ivory's age
= 3 p - 5
= 3 x 4 - 5
= 12 - 5
= 7
Answer(s): 7
