The ratio of the number of blue stickers to green stickers is 3 : 2.
After Adam gives away 77 blue stickers and gives away 54 green stickers,
the ratio becomes of the number of blue stickers to green stickers is 7 : 4.
How many stickers does Adam have now?
|
Make p the same (1) x 4 = (3) |
(1) Blue |
(2) Green |
Make p the same (2) x 7 = (4) |
Before |
12 u |
3 u |
2 u |
14 u |
Change |
- 308 |
- 77 |
- 54 |
- 378 |
After |
28 p |
7 p |
4 p |
28 p |
3 u - 77 = 7 p --- (1)
2 u - 54 = 4 p --- (2)
Make p the same.
(1) x 4
12 u - 308 = 28 p --- (3)
(2) x 7
14 u - 378 = 28 p --- (4)
(4) = (3)
14 u - 378 = 12 u - 308
14 u - 12 u = 378 - 308
2 u = 70
1 u = 70 ÷ 2 = 35
Number of stickers that Adam has now
= 3 u - 77 + 2 u - 54
= 5 u - 131
= 5 x 35 - 131
= 175 - 131
= 44
Answer(s): 44