Elijah is 20 years older than his son. 3 years from now, his son will be
13 of his age while his child will be
35 of his son. Express his child’s present age as a fraction of Elijah's present age. Leave your answer in its simplest form.
| |
Elijah |
Elijah's son |
Elijah's child |
Difference between
Elijah and Elijah's son |
| Before |
15 u - 3 |
5 u - 3 |
3 u - 3 |
20 |
| Change |
+ 3 |
+ 3 |
+ 3 |
|
After
|
3x5 |
1x5 |
|
|
| |
5x1 |
3x1 |
|
Comparing Elijah, his son and his child
in the end |
15 u |
5 u |
3 u |
10 u |
The repeated identity is the age of Elijah's son. LCM of 1 and 5 is 5.
The difference in age between Elijah and Elijah's son remains unchanged.
Difference in age between Elijah and Elijah's son
= 15 u - 5 u
= 10 u
10 u = 20
1 u = 20 ÷ 10 = 2
His child's present age
= 3 u - 3
= 3 x 2 - 3
= 6 - 3
= 3
Elijah's present age
= 15 u - 3
= 15 x 2 - 3
= 30 - 3
= 27
His child's present age as a fraction of Elijah's present age
=
327=
19 Answer(s):
19 
