Yoko had 135 more buttons than Betty. After Betty gave away
15 of her buttons, Yoko had twice as many buttons as Betty. How many buttons did Betty have at first?
| |
Yoko |
Betty |
Comparing Yoko
and Betty at first |
135 more |
|
| Before |
8 u |
5 u |
| Change |
|
- 1 u |
| After |
|
4 u |
Comparing Yoko
and Betty in the end |
2x4 =
8 u |
1x4 =
4 u |
The number of buttons that Yoko had at first and in the end remains unchanged. Make the number of buttons that Yoko had the same. LCM of 8 and 2 is 8.
Number of buttons that Yoko had more than Betty at first
= 8 u - 5 u
= 3 u
3 u = 135
1 u = 135 ÷ 3 = 45
Number of buttons that Betty had at first
= 5 u
= 5 x 45
= 225
Answer(s): 225
