Zane had some buttons at first. After he bought another 60 buttons, he had four times as many buttons as before. How many buttons did Zane have at first?
| |
Buttons |
| Before |
1 u |
| Change |
+ 60 |
| After |
1 u + 60 = 4 u |
Number of buttons after he bought = 1 u + 60
Number of buttons that is four times as many buttons as before = 4 x 1 u = 4 u
4 u = 1 u + 60
4 u - 1 u = 60
3 u = 60
1 u = 60 ÷ 3 = 20
Number of stickers that Kim had at first
= 1 u
= 20
Answer(s): 20
