Adam and Bryan have some stickers in the ratio of 3 : 2.
When Adam gives away 42 stickers,
the ratio of the stickers becomes 5 : 8.
- How many stickers do they have at first?
- How many stickers do they have in the end?
|
Adam |
Bryan |
Before |
3 x 4 = 12 u |
2 x 4 = 8 u |
Change |
- 42 |
No change |
After |
5 x 1 = 5 u |
8 x 1 = 8 u |
(a)
The number of stickers that Bryan has remains unchanged.
Make the number of stickers that Bryan has the same using LCM of 2 and 8.
LCM of 2 and 8 = 8
Number of stickers that Adam gives away
= 12 u - 5 u
= 7 u
7 u = 42
1 u = 42 ÷ 7 = 6
Number of stickers that they have at first
= 12 u + 8 u
= 20 u
= 20 x 6
= 120
(b)
Number of stickers that they have in the end
= 5 u + 8 u
= 13 u
= 13 x 6
= 78
Answer(s): (a) 120; (b) 78