Risa will be 80 years old in 8 years' time. Now, Jade's age is 56 of Risa's age. What was Jade's age when she was 3 years more than 75% of Risa's age?
| |
Jade |
Risa |
Difference |
| Before |
3 p + 3 |
4 p |
1 p - 3 |
| Change 1 |
+ ? |
+ ? |
|
| After 1 (Now) |
5 u |
6 u |
1 u |
| Change 2 |
+ 8 |
+ 8 |
|
| After |
5 u + 8 |
80 |
|
Risa's age in 8 years' time = 6 u + 8
6 u + 8 = 80
6 u = 80 - 8
6 u = 72
1 u = 72 ÷ 6 = 12
Difference between Risa's age and Jade's age
= 1 u
= 12
75% =
75100 =
34 Difference in Risa's age and Jade's age at first
= 4 p - (3 p + 3)
= 1 p - 3
The difference in age between Risa and Jade remains unchanged.
1 p - 3 = 12
1 p = 12 + 3 = 15
Jade's age when she was 3 years more than 75% of Risa's age
= 3 p + 3
= 3 x 15 + 3
= 45 + 3
= 48
Answer(s): 48
