The ratio of the number of blue stickers to red stickers is 3 : 2.
After Adam gives away 36 blue stickers and gives away 29 red stickers,
the ratio becomes of the number of blue stickers to red stickers is 7 : 3.
How many stickers does Adam have now?
|
Make p the same (1) x 3 = (3) |
(1) Blue |
(2) Red |
Make p the same (2) x 7 = (4) |
Before |
9 u |
3 u |
2 u |
14 u |
Change |
- 108 |
- 36 |
- 29 |
- 203 |
After |
21 p |
7 p |
3 p |
21 p |
3 u - 36 = 7 p --- (1)
2 u - 29 = 3 p --- (2)
Make p the same.
(1) x 3
9 u - 108 = 21 p --- (3)
(2) x 7
14 u - 203 = 21 p --- (4)
(4) = (3)
14 u - 203 = 9 u - 108
14 u - 9 u = 203 - 108
5 u = 95
1 u = 95 ÷ 5 = 19
Number of stickers that Adam has now
= 3 u - 36 + 2 u - 29
= 5 u - 65
= 5 x 19 - 65
= 95 - 65
= 30
Answer(s): 30