The ratio of Evelyn's marbles to Lilian's marbles at first was 3 : 7. After Evelyn gave Lilian 106 marbles, the ratio of Evelyn's marbles to Lilian's marbles is 1 : 3. What was the number of marbles they had in all?
|
Evelyn |
Lilian |
Total |
Before |
3x4 = 12 u |
7x4 = 28 u
|
10x4 = 40 u |
Change |
- 106 |
+ 106 |
|
After |
1x10 = 10 u |
3x10 = 30 u |
4x10 = 40 u |
Number of marbles that Evelyn gave Lilian
= 12 u - 10 u
= 2 u
2 u = 106
1 u = 106 ÷ 2 = 53
Total number of marbles that they had
= 40 u
= 40 x 53
= 2120
Answer(s): 2120