Reggie had some pens at first. After he bought another 90 pens, he had four times as many pens as before. How many pens did Reggie have at first?
| |
Pens |
| Before |
1 u |
| Change |
+ 90 |
| After |
1 u + 90 = 4 u |
Number of pens after he bought = 1 u + 90
Number of pens that is four times as many pens as before = 4 x 1 u = 4 u
4 u = 1 u + 90
4 u - 1 u = 90
3 u = 90
1 u = 90 ÷ 3 = 30
Number of stickers that Kim had at first
= 1 u
= 30
Answer(s): 30
