Adam and Bryan have some stickers in the ratio of 4 : 5.
When Adam buys another 42 stickers,
the ratio of the stickers becomes 3 : 2.
- How many stickers do they have at first?
- How many stickers do they have in the end?
|
Bryan |
Adam |
Before |
4 x 2 = 8 u |
5 x 2 = 10 u |
Change |
+ 42 |
No change |
After |
3 x 5 = 15 u |
2 x 5 = 10 u |
(a)
The number of stickers that Adam has remains unchanged.
Make the number of stickers that Adam has the same using LCM of 5 and 2.
LCM of 5 and 2 = 10
Number of stickers that Bryan buys
= 15 u - 8 u
= 7 u
7 u = 42
1 u = 42 ÷ 7 = 6
Number of stickers that they have at first
= 8 u + 10 u
= 18 u
= 18 x 6
= 108
(b)
Number of stickers that they have in the end
= 15 u + 10 u
= 25 u
= 25 x 6
= 150
Answer(s): (a) 108; (b) 150