The ratio of Levi's marbles to Jonathan's marbles at first was 3 : 7. After Levi gave Jonathan 30 marbles, the ratio of Levi's marbles to Jonathan's marbles is 1 : 4. What was the number of marbles they had altogether?
|
Levi |
Jonathan |
Total |
Before |
3x5 = 15 u |
7x5 = 35 u
|
10x5 = 50 u |
Change |
- 30 |
+ 30 |
|
After |
1x10 = 10 u |
4x10 = 40 u |
5x10 = 50 u |
Number of marbles that Levi gave Jonathan
= 15 u - 10 u
= 5 u
5 u = 30
1 u = 30 ÷ 5 = 6
Total number of marbles that they had
= 50 u
= 50 x 6
= 300
Answer(s): 300