Adam has red and green stickers in the ratio of 1 : 5.
When 12 green stickers are replaced with the same number of red stickers,
the ratio of the number of red and green stickers will be 3 : 7
How many stickers are there altogether?
|
Red |
Green |
Total |
Before |
1 x 5 = 5 u |
5 x 5 = 25 u |
6 x 5 = 30 u |
Change |
+ 12 |
- 12 |
|
After |
3 x 3 = 9 u |
7 x 3 = 21 u |
10 x 3 = 30 u |
When 12 green stickers are replaced with the same number of red stickers, the total number of stickers remains unchanged.
Make the total number of stickers the same using the LCM of 6 and 10.
LCM of 6 and 10 = 30
Number of green stickers that is replaced by red stickers
= 9 u - 5 u
= 4 u
4 u = 12
1 u = 12 ÷ 4 = 3
Total number of stickers
= 30 u
= 30 x 3
= 90
Answer(s): 90