Cindy had 40 more buttons than Barbara. After Cindy gave away
35 of her buttons and Barbara gave away
34 of her buttons, Barbara had 40 less buttons than Cindy. How many buttons did Cindy have at first?
| |
Cindy |
Barbara |
Comparing Cindy and
Barbara at first |
40 more |
|
| Before |
5x4 |
+ 40 |
4x5 |
| Change |
- 3x4 |
- 24 |
- 3x5 |
| After |
2x4 |
+ 16 |
1x5 |
Comparing Cindy and
Barbara in the end |
|
40 less |
| |
Cindy |
Barbara |
| Before |
20 u + 40 |
20 u |
| Change |
- 12 u - 24 |
- 15 u |
| After |
8 u + 16 |
5 u |
35 x 40 = 24
40 - 24 = 16
Barbara had 40 less buttons than Cindy in the end. So, if Barbara had another 40 buttons in the end, the number of buttons that Barbara and Cindy each had would be the same.
8 u + 16 = 5 u + 40
8 u - 5 u = 40 - 16
3 u = 24
1 u = 24 ÷ 3 = 8
Number of buttons that Cindy had at first
= 20 u + 40
= 20 x 8 + 40
= 160 + 40
= 200
Answer(s): 200
