The ratio of the number of blue stickers to green stickers is 2 : 1.
After Adam buys another 20 blue stickers and 90 green stickers,
the ratio becomes of the number of blue stickers to green stickers is 8 : 5.
How many stickers does Adam have now?
|
Make p the same (1) x 5 = (3) |
(1) Blue |
(2) Green |
Make p the same (2) x 8 = (4) |
Before |
10 u |
2 u |
1 u |
8 u |
Change |
+ 100 |
+ 20 |
+ 90 |
+ 720 |
After |
10 u + 100 |
2 u + 20 |
1 u + 90 |
8 u + 720 |
Comparing the blue stickers and the green stickers in the end |
40 p |
8 p |
5 p |
40 p |
2 u + 20 = 8 p --- (1)
1 u + 90 = 5 p --- (2)
Make p the same by using the LCM of 5 and 8.
LCM of 5 and 8 is 40.
(1)
x 5 10 u + 100 = 40 p --- (3)
(2)
x 8 8 u + 720 = 40 p --- (4)
(3) = (4)
10 u + 100 = 8 u + 720
10 u - 8 u = 720 - 100
2 u = 620
1 u = 620 ÷ 2 = 310
Number of stickers that Adam has now
= 2 u + 20 + 1 u + 90
= 2 u + 1 u + 20 + 90
= 3 u + 110
= 3 x 310 + 110
= 930 + 110
= 1040
Answer(s): 1040