Olivia will be 48 years old in 18 years' time. Now, Shiyun's age is 12 of Olivia's age. What was Shiyun's age when she was 8 years less than 75% of Olivia's age?
| |
Shiyun |
Olivia |
Difference |
| Before |
3 p - 8 |
4 p |
1 p + 8 |
| Change 1 |
+ ? |
+ ? |
|
| After 1 (Now) |
1 u |
2 u |
1 u |
| Change 2 |
+ 18 |
+ 18 |
|
| After |
1 u + 18 |
48 |
|
Olivia's age in 18 years' time = 2 u + 18
2 u + 18 = 48
2 u = 48 - 18
2 u = 30
1 u = 30 ÷ 2 = 15
Difference between Olivia's age and Shiyun's age
= 1 u
= 15
75% =
75100 =
34 Difference in Olivia's age and Shiyun's age at first
= 4 p - (3 p - 8)
= 1 p + 8
The difference in age between Olivia and Shiyun remains unchanged.
1 p + 8 = 15
1 p = 15 - 8 = 7
Shiyun's age when she was 8 years less than 75% of Olivia's age
= 3 p - 8
= 3 x 7 - 8
= 21 - 8
= 13
Answer(s): 13
