The ratio of the number of blue stickers to green stickers is 4 : 3.
After Adam gives away 39 blue stickers and gives away 34 green stickers,
the ratio becomes of the number of blue stickers to green stickers is 9 : 2.
How many stickers does Adam have now?
|
Make p the same (1) x 2 = (3) |
(1) Blue |
(2) Green |
Make p the same (2) x 9 = (4) |
Before |
8 u |
4 u |
3 u |
27 u |
Change |
- 78 |
- 39 |
- 34 |
- 306 |
After |
18 p |
9 p |
2 p |
18 p |
4 u - 39 = 9 p --- (1)
3 u - 34 = 2 p --- (2)
Make p the same.
(1) x 2
8 u - 78 = 18 p --- (3)
(2) x 9
27 u - 306 = 18 p --- (4)
(4) = (3)
27 u - 306 = 8 u - 78
27 u - 8 u = 306 - 78
19 u = 228
1 u = 228 ÷ 19 = 12
Number of stickers that Adam has now
= 4 u - 39 + 3 u - 34
= 7 u - 73
= 7 x 12 - 73
= 84 - 73
= 11
Answer(s): 11