The ratio of Mia's erasers to Scarlett's erasers at first was 3 : 7. After Mia gave Scarlett 74 erasers, the ratio of Mia's erasers to Scarlett's erasers is 1 : 3. What was the number of erasers they had in all?
|
Mia |
Scarlett |
Total |
Before |
3x4 = 12 u |
7x4 = 28 u
|
10x4 = 40 u |
Change |
- 74 |
+ 74 |
|
After |
1x10 = 10 u |
3x10 = 30 u |
4x10 = 40 u |
Number of erasers that Mia gave Scarlett
= 12 u - 10 u
= 2 u
2 u = 74
1 u = 74 ÷ 2 = 37
Total number of erasers that they had
= 40 u
= 40 x 37
= 1480
Answer(s): 1480