The ratio of Evelyn's marbles to Nathan's marbles at first was 3 : 7. After Evelyn gave Nathan 60 marbles, the ratio of Evelyn's marbles to Nathan's marbles is 1 : 4. What was the number of marbles they had altogether?
|
Evelyn |
Nathan |
Total |
Before |
3x5 = 15 u |
7x5 = 35 u
|
10x5 = 50 u |
Change |
- 60 |
+ 60 |
|
After |
1x10 = 10 u |
4x10 = 40 u |
5x10 = 50 u |
Number of marbles that Evelyn gave Nathan
= 15 u - 10 u
= 5 u
5 u = 60
1 u = 60 ÷ 5 = 12
Total number of marbles that they had
= 50 u
= 50 x 12
= 600
Answer(s): 600