The ratio of the number of blue stickers to red stickers is 3 : 2.
After Adam gives away 57 blue stickers and gives away 30 red stickers,
the ratio becomes of the number of blue stickers to red stickers is 5 : 2.
How many stickers does Adam have now?
|
Make p the same (1) x 2 = (3) |
(1) Blue |
(2) Red |
Make p the same (2) x 5 = (4) |
Before |
6 u |
3 u |
2 u |
10 u |
Change |
- 114 |
- 57 |
- 30 |
- 150 |
After |
10 p |
5 p |
2 p |
10 p |
3 u - 57 = 5 p --- (1)
2 u - 30 = 2 p --- (2)
Make p the same.
(1) x 2
6 u - 114 = 10 p --- (3)
(2) x 5
10 u - 150 = 10 p --- (4)
(4) = (3)
10 u - 150 = 6 u - 114
10 u - 6 u = 150 - 114
4 u = 36
1 u = 36 ÷ 4 = 9
Number of stickers that Adam has now
= 3 u - 57 + 2 u - 30
= 5 u - 87
= 5 x 9 - 87
= 45 - 87
= -42
Answer(s): -42