The ratio of the number of red stickers to green stickers is 3 : 2.
After Adam gives away 42 red stickers and gives away 92 green stickers,
the ratio becomes of the number of red stickers to green stickers is 7 : 4.
How many stickers does Adam have now?
|
Make p the same (1) x 4 = (3) |
(1) Red |
(2) Green |
Make p the same (2) x 7 = (4) |
Before |
12 u |
3 u |
2 u |
14 u |
Change |
- 168 |
- 42 |
- 92 |
- 644 |
After |
28 p |
7 p |
4 p |
28 p |
3 u - 42 = 7 p --- (1)
2 u - 92 = 4 p --- (2)
Make p the same.
(1) x 4
12 u - 168 = 28 p --- (3)
(2) x 7
14 u - 644 = 28 p --- (4)
(4) = (3)
14 u - 644 = 12 u - 168
14 u - 12 u = 644 - 168
2 u = 476
1 u = 476 ÷ 2 = 238
Number of stickers that Adam has now
= 3 u - 42 + 2 u - 92
= 5 u - 134
= 5 x 238 - 134
= 1190 - 134
= 1056
Answer(s): 1056