The ratio of the number of blue stickers to green stickers is 3 : 1.
After Adam buys another 49 green stickers and gives away 37 blue stickers,
the ratio becomes of the number of blue stickers to green stickers is 7 : 3.
How many stickers does Adam have now?
|
Make p the same (1) x 3 = (3) |
(1) Blue |
(2) Green |
Make p the same (2) x 7 = (4) |
Before |
9 u |
3 u |
1 u |
7 u |
Change |
- 111 |
- 37 |
+ 49 |
+ 343 |
After |
21 p |
7 p |
3 p |
21 p |
3 u + 49 = 7 p --- (1)
1 u - 37 = 3 p --- (2)
Make p the same.
(1)
x 39 u - 111 = 21 p --- (3)
(2)
x 77 u + 343 = 21 p --- (4)
(3) = (4)
9 u - 111 = 7 u + 343
9 u - 7 u = 111 + 343
2 u = 454
1 u = 454 ÷ 2 = 227
Number of stickers that Adam have now
= 3 u + 49 + 1 u - 37
= 3 u + 1 u + 49 - 37
= 4 u + 12
= 4 x 227 + 12
= 908 + 12
= 920
Answer(s): 920