The ratio of the number of red stickers to green stickers is 2 : 1.
After Adam buys another 10 red stickers and 30 green stickers,
the ratio becomes of the number of red stickers to green stickers is 4 : 3.
How many stickers does Adam have now?
|
Make p the same (1) x 3 = (3) |
(1) Red |
(2) Green |
Make p the same (2) x 4 = (4) |
Before |
6 u |
2 u |
1 u |
4 u |
Change |
+ 30 |
+ 10 |
+ 30 |
+ 120 |
After |
6 u + 30 |
2 u + 10 |
1 u + 30 |
4 u + 120 |
Comparing the red stickers and the green stickers in the end |
12 p |
4 p |
3 p |
12 p |
2 u + 10 = 4 p --- (1)
1 u + 30 = 3 p --- (2)
Make p the same by using the LCM of 3 and 4.
LCM of 3 and 4 is 12.
(1)
x 3 6 u + 30 = 12 p --- (3)
(2)
x 4 4 u + 120 = 12 p --- (4)
(3) = (4)
6 u + 30 = 4 u + 120
6 u - 4 u = 120 - 30
2 u = 90
1 u = 90 ÷ 2 = 45
Number of stickers that Adam has now
= 2 u + 10 + 1 u + 30
= 2 u + 1 u + 10 + 30
= 3 u + 40
= 3 x 45 + 40
= 135 + 40
= 175
Answer(s): 175