The ratio of Nathan's buttons to Ellie's buttons at first was 2 : 5. After Nathan gave Ellie 120 buttons, the ratio of Nathan's buttons to Ellie's buttons is 1 : 4. What was the number of buttons they had in total?
|
Nathan |
Ellie |
Total |
Before |
2x5 = 10 u |
5x5 = 25 u
|
7x5 = 35 u |
Change |
- 120 |
+ 120 |
|
After |
1x7 = 7 u |
4x7 = 28 u |
5x7 = 35 u |
Number of buttons that Nathan gave Ellie
= 10 u - 7 u
= 3 u
3 u = 120
1 u = 120 ÷ 3 = 40
Total number of buttons that they had
= 35 u
= 35 x 40
= 1400
Answer(s): 1400