Charlie and Adam have some stickers in the ratio of 7 : 2.
When Charlie gives away 39 stickers,
the ratio of the stickers becomes 4 : 3.
- How many stickers do they have at first?
- How many stickers do they have in the end?
|
Charlie |
Adam |
Before |
7 x 3 = 21 u |
2 x 3 = 6 u |
Change |
- 39 |
No change |
After |
4 x 2 = 8 u |
3 x 2 = 6 u |
(a)
The number of stickers that Adam has remains unchanged.
Make the number of stickers that Adam has the same using LCM of 2 and 3.
LCM of 2 and 3 = 6
Number of stickers that Charlie gives away
= 21 u - 8 u
= 13 u
13 u = 39
1 u = 39 ÷ 13 = 3
Number of stickers that they have at first
= 21 u + 6 u
= 27 u
= 27 x 3
= 81
(b)
Number of stickers that they have in the end
= 8 u + 6 u
= 14 u
= 14 x 3
= 42
Answer(s): (a) 81; (b) 42