Mary will be 62 years old in 2 years' time. Now, Vanessa's age is 45 of Mary's age. What was Vanessa's age when she was 7 years less than 90% of Mary's age?
| |
Vanessa |
Mary |
Difference |
| Before |
9 p - 7 |
10 p |
1 p + 7 |
| Change 1 |
+ ? |
+ ? |
|
| After 1 (Now) |
4 u |
5 u |
1 u |
| Change 2 |
+ 2 |
+ 2 |
|
| After |
4 u + 2 |
62 |
|
Mary's age in 2 years' time = 5 u + 2
5 u + 2 = 62
5 u = 62 - 2
5 u = 60
1 u = 60 ÷ 5 = 12
Difference between Mary's age and Vanessa's age
= 1 u
= 12
90% =
90100 =
910 Difference in Mary's age and Vanessa's age at first
= 10 p - (9 p - 7)
= 1 p + 7
The difference in age between Mary and Vanessa remains unchanged.
1 p + 7 = 12
1 p = 12 - 7 = 5
Vanessa's age when she was 7 years less than 90% of Mary's age
= 9 p - 7
= 9 x 5 - 7
= 45 - 7
= 38
Answer(s): 38
