The ratio of the number of red stickers to blue stickers is 4 : 1.
After Adam buys another 10 red stickers and 90 blue stickers,
the ratio becomes of the number of red stickers to blue stickers is 6 : 5.
How many stickers does Adam have now?
|
Make p the same (1) x 5 = (3) |
(1) Red |
(2) Blue |
Make p the same (2) x 6 = (4) |
Before |
20 u |
4 u |
1 u |
6 u |
Change |
+ 50 |
+ 10 |
+ 90 |
+ 540 |
After |
20 u + 50 |
4 u + 10 |
1 u + 90 |
6 u + 540 |
Comparing the red stickers and the blue stickers in the end |
30 p |
6 p |
5 p |
30 p |
4 u + 10 = 6 p --- (1)
1 u + 90 = 5 p --- (2)
Make p the same by using the LCM of 5 and 6.
LCM of 5 and 6 is 30.
(1)
x 5 20 u + 50 = 30 p --- (3)
(2)
x 6 6 u + 540 = 30 p --- (4)
(3) = (4)
20 u + 50 = 6 u + 540
20 u - 6 u = 540 - 50
14 u = 490
1 u = 490 ÷ 14 = 35
Number of stickers that Adam has now
= 4 u + 10 + 1 u + 90
= 4 u + 1 u + 10 + 90
= 5 u + 100
= 5 x 35 + 100
= 175 + 100
= 275
Answer(s): 275