The ratio of the number of red stickers to green stickers is 4 : 1.
After Adam buys another 47 green stickers and gives away 20 red stickers,
the ratio becomes of the number of red stickers to green stickers is 4 : 3.
How many stickers does Adam have now?
|
Make p the same (1) x 3 = (3) |
(1) Red |
(2) Green |
Make p the same (2) x 4 = (4) |
Before |
12 u |
4 u |
1 u |
4 u |
Change |
- 60 |
- 20 |
+ 47 |
+ 188 |
After |
12 p |
4 p |
3 p |
12 p |
4 u + 47 = 4 p --- (1)
1 u - 20 = 3 p --- (2)
Make p the same.
(1)
x 312 u - 60 = 12 p --- (3)
(2)
x 44 u + 188 = 12 p --- (4)
(3) = (4)
12 u - 60 = 4 u + 188
12 u - 4 u = 60 + 188
8 u = 248
1 u = 248 ÷ 8 = 31
Number of stickers that Adam have now
= 4 u + 47 + 1 u - 20
= 4 u + 1 u + 47 - 20
= 5 u + 27
= 5 x 31 + 27
= 155 + 27
= 182
Answer(s): 182