Elijah's age is
25 of his grandaunt's. His grandaunt will be 61 years old in 11 years' time. In how many years' time will Elijah's age be
710 that of his grandaunt's?
| |
Elijah |
His grandaunt |
Difference |
| Before |
2x1 =
2 u |
5x1 =
5 u |
3x1 =
3 u |
| Change 1 |
+ 11 |
+ 11 |
|
| After |
|
61 |
|
| Change 2 |
+ ? |
+ ? |
|
| After 2 |
7x1 =
7 u |
10x1 =
10 u |
3x1 =
3 u |
The age difference between Elijah and his grandaunt remains unchanged.
LCM of 3 and 3 is 3.
5 u + 11 = 61
5 u = 61 - 11
5 u = 50
1 u = 50 ÷ 5 = 10
Number of years' time when Elijah's age will be
710 that of his grandaunt's age
= 7 u - 2 u
= 5 u
= 5 x 10
= 50
Answer(s): 50
