Adam and Bryan have some stickers in the ratio of 8 : 5.
When Adam buys another 75 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 |
5 x 4 = 20 u |
Change |
+ 75 |
No change |
After |
7 x 5 = 35 u |
4 x 5 = 20 u |
(a)
The number of stickers that Bryan has remains unchanged.
Make the number of stickers that Bryan has the same using LCM of 5 and 4.
LCM of 5 and 4 = 20
Number of stickers that Adam buys
= 35 u - 32 u
= 3 u
3 u = 75
1 u = 75 ÷ 3 = 25
Number of stickers that they have at first
= 32 u + 20 u
= 52 u
= 52 x 25
= 1300
(b)
Number of stickers that they have in the end
= 35 u + 20 u
= 55 u
= 55 x 25
= 1375
Answer(s): (a) 1300; (b) 1375