Irene had 96 more buttons than Lucy. After Irene gave away
14 of her buttons and Lucy gave away
25 of her buttons, Lucy had 90 less buttons than Irene. How many buttons did Irene have at first?
| |
Irene |
Lucy |
Comparing Irene and
Lucy at first |
96 more |
|
| Before |
4x5 |
+ 96 |
5x4 |
| Change |
- 1x5 |
- 24 |
- 2x4 |
| After |
3x5 |
+ 72 |
3x4 |
Comparing Irene and
Lucy in the end |
|
90 less |
| |
Irene |
Lucy |
| Before |
20 u + 96 |
20 u |
| Change |
- 5 u - 24 |
- 8 u |
| After |
15 u + 72 |
12 u |
14 x 96 = 24
96 - 24 = 72
Lucy had 90 less buttons than Irene in the end. So, if Lucy had another 90 buttons in the end, the number of buttons that Lucy and Irene each had would be the same.
15 u + 72 = 12 u + 90
15 u - 12 u = 90 - 72
3 u = 18
1 u = 18 ÷ 3 = 6
Number of buttons that Irene had at first
= 20 u + 96
= 20 x 6 + 96
= 120 + 96
= 216
Answer(s): 216
