The ratio of the number of green stickers to blue stickers is 3 : 2.
After Adam gives away 69 green stickers and gives away 22 blue stickers,
the ratio becomes of the number of green stickers to blue stickers is 7 : 2.
How many stickers does Adam have now?
|
Make p the same (1) x 2 = (3) |
(1) Green |
(2) Blue |
Make p the same (2) x 7 = (4) |
Before |
6 u |
3 u |
2 u |
14 u |
Change |
- 138 |
- 69 |
- 22 |
- 154 |
After |
14 p |
7 p |
2 p |
14 p |
3 u - 69 = 7 p --- (1)
2 u - 22 = 2 p --- (2)
Make p the same.
(1) x 2
6 u - 138 = 14 p --- (3)
(2) x 7
14 u - 154 = 14 p --- (4)
(4) = (3)
14 u - 154 = 6 u - 138
14 u - 6 u = 154 - 138
8 u = 16
1 u = 16 ÷ 8 = 2
Number of stickers that Adam has now
= 3 u - 69 + 2 u - 22
= 5 u - 91
= 5 x 2 - 91
= 10 - 91
= -81
Answer(s): -81