The ratio of the number of blue stickers to red stickers is 3 : 1.
After Adam buys another 30 blue stickers and 40 red stickers,
the ratio becomes of the number of blue stickers to red stickers is 4 : 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 4 = (4) |
Before |
9 u |
3 u |
1 u |
4 u |
Change |
+ 90 |
+ 30 |
+ 40 |
+ 160 |
After |
9 u + 90 |
3 u + 30 |
1 u + 40 |
4 u + 160 |
Comparing the blue stickers and the red stickers in the end |
12 p |
4 p |
3 p |
12 p |
3 u + 30 = 4 p --- (1)
1 u + 40 = 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 9 u + 90 = 12 p --- (3)
(2)
x 4 4 u + 160 = 12 p --- (4)
(3) = (4)
9 u + 90 = 4 u + 160
9 u - 4 u = 160 - 90
5 u = 70
1 u = 70 ÷ 5 = 14
Number of stickers that Adam has now
= 3 u + 30 + 1 u + 40
= 3 u + 1 u + 30 + 40
= 4 u + 70
= 4 x 14 + 70
= 56 + 70
= 126
Answer(s): 126