Adam has blue and red stickers in the ratio of 2 : 5.
When 68 red stickers are replaced with the same number of blue stickers,
the ratio of the number of blue and red stickers will be 2 : 3
How many stickers are there altogether?
|
Blue |
Red |
Total |
Before |
2 x 5 = 10 u |
5 x 5 = 25 u |
7 x 5 = 35 u |
Change |
+ 68 |
- 68 |
|
After |
2 x 7 = 14 u |
3 x 7 = 21 u |
5 x 7 = 35 u |
When 68 red stickers are replaced with the same number of blue stickers, the total number of stickers remains unchanged.
Make the total number of stickers the same using the LCM of 7 and 5.
LCM of 7 and 5 = 35
Number of red stickers that is replaced by blue stickers
= 14 u - 10 u
= 4 u
4 u = 68
1 u = 68 ÷ 4 = 17
Total number of stickers
= 35 u
= 35 x 17
= 595
Answer(s): 595