The ratio of the number of green stickers to blue stickers is 3 : 2.
After Adam gives away 81 green stickers and gives away 66 blue stickers,
the ratio becomes of the number of green stickers to blue stickers is 9 : 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 9 = (4) |
Before |
6 u |
3 u |
2 u |
18 u |
Change |
- 162 |
- 81 |
- 66 |
- 594 |
After |
18 p |
9 p |
2 p |
18 p |
3 u - 81 = 9 p --- (1)
2 u - 66 = 2 p --- (2)
Make p the same.
(1) x 2
6 u - 162 = 18 p --- (3)
(2) x 9
18 u - 594 = 18 p --- (4)
(4) = (3)
18 u - 594 = 6 u - 162
18 u - 6 u = 594 - 162
12 u = 432
1 u = 432 ÷ 12 = 36
Number of stickers that Adam has now
= 3 u - 81 + 2 u - 66
= 5 u - 147
= 5 x 36 - 147
= 180 - 147
= 33
Answer(s): 33