Nicole will be 110 years old in 20 years' time. Now, Irene's age is 56 of Nicole's age. What was Irene's age when she was 5 years less than 90% of Nicole's age?
| |
Irene |
Nicole |
Difference |
| Before |
9 p - 5 |
10 p |
1 p + 5 |
| Change 1 |
+ ? |
+ ? |
|
| After 1 (Now) |
5 u |
6 u |
1 u |
| Change 2 |
+ 20 |
+ 20 |
|
| After |
5 u + 20 |
110 |
|
Nicole's age in 20 years' time = 6 u + 20
6 u + 20 = 110
6 u = 110 - 20
6 u = 90
1 u = 90 ÷ 6 = 15
Difference between Nicole's age and Irene's age
= 1 u
= 15
90% =
90100 =
910 Difference in Nicole's age and Irene's age at first
= 10 p - (9 p - 5)
= 1 p + 5
The difference in age between Nicole and Irene remains unchanged.
1 p + 5 = 15
1 p = 15 - 5 = 10
Irene's age when she was 5 years less than 90% of Nicole's age
= 9 p - 5
= 9 x 10 - 5
= 90 - 5
= 85
Answer(s): 85
