The ratio of Gavin's buttons to Emily's buttons at first was 3 : 7. After Gavin gave Emily 10 buttons, the ratio of Gavin's buttons to Emily's buttons is 1 : 4. What was the number of buttons they had altogether?
| |
Gavin |
Emily |
Total |
| Before |
3x5 =
15 u |
7x5 =
35 u
|
10x5 =
50 u |
| Change |
- 10 |
+ 10 |
|
| After |
1x10 =
10 u |
4x10 =
40 u |
5x10 =
50 u |
Number of buttons that Gavin gave Emily
= 15 u - 10 u
= 5 u
5 u = 10
1 u = 10 ÷ 5 = 2
Total number of buttons that they had
= 50 u
= 50 x 2
= 100
Answer(s): 100
