Adam and Bryan have some stickers in the ratio of 8 : 7.
When Adam buys another 51 stickers,
the ratio of the stickers becomes 7 : 4.
- How many stickers do they have at first?
- How many stickers do they have in the end?
|
Adam |
Bryan |
Before |
8 x 4 = 32 u |
7 x 4 = 28 u |
Change |
+ 51 |
No change |
After |
7 x 7 = 49 u |
4 x 7 = 28 u |
(a)
The number of stickers that Bryan has remains unchanged.
Make the number of stickers that Bryan has the same using LCM of 7 and 4.
LCM of 7 and 4 = 28
Number of stickers that Adam buys
= 49 u - 32 u
= 17 u
17 u = 51
1 u = 51 ÷ 17 = 3
Number of stickers that they have at first
= 32 u + 28 u
= 60 u
= 60 x 3
= 180
(b)
Number of stickers that they have in the end
= 49 u + 28 u
= 77 u
= 77 x 3
= 231
Answer(s): (a) 180; (b) 231