The ratio of the number of green stickers to red stickers is 4 : 1.
After Adam buys another 39 red stickers and gives away 12 green stickers,
the ratio becomes of the number of green stickers to red stickers is 5 : 2.
How many stickers does Adam have now?
|
Make p the same (1) x 2 = (3) |
(1) Green |
(2) Red |
Make p the same (2) x 5 = (4) |
Before |
8 u |
4 u |
1 u |
5 u |
Change |
- 24 |
- 12 |
+ 39 |
+ 195 |
After |
10 p |
5 p |
2 p |
10 p |
4 u + 39 = 5 p --- (1)
1 u - 12 = 2 p --- (2)
Make p the same.
(1)
x 28 u - 24 = 10 p --- (3)
(2)
x 55 u + 195 = 10 p --- (4)
(3) = (4)
8 u - 24 = 5 u + 195
8 u - 5 u = 24 + 195
3 u = 219
1 u = 219 ÷ 3 = 73
Number of stickers that Adam have now
= 4 u + 39 + 1 u - 12
= 4 u + 1 u + 39 - 12
= 5 u + 27
= 5 x 73 + 27
= 365 + 27
= 392
Answer(s): 392