Adam and Bryan have some stickers in the ratio of 3 : 4.
When Adam buys another 76 stickers,
the ratio of the stickers becomes 7 : 3.
- How many stickers do they have at first?
- How many stickers do they have in the end?
|
Bryan |
Adam |
Before |
3 x 3 = 9 u |
4 x 3 = 12 u |
Change |
+ 76 |
No change |
After |
7 x 4 = 28 u |
3 x 4 = 12 u |
(a)
The number of stickers that Adam has remains unchanged.
Make the number of stickers that Adam has the same using LCM of 4 and 3.
LCM of 4 and 3 = 12
Number of stickers that Bryan buys
= 28 u - 9 u
= 19 u
19 u = 76
1 u = 76 ÷ 19 = 4
Number of stickers that they have at first
= 9 u + 12 u
= 21 u
= 21 x 4
= 84
(b)
Number of stickers that they have in the end
= 28 u + 12 u
= 40 u
= 40 x 4
= 160
Answer(s): (a) 84; (b) 160