Last week, Ethan had a total of 238 black and white staplers. Two weeks later, he sold
34 of all the black staplers and 13 white staplers. Now he has the same number of black and white staplers. How many staplers does he have in the end?
| |
Black |
White |
Total |
| Before |
4 u |
1 u + 13 |
5 u + 13 |
| Change |
- 3 u |
- 13 |
|
| After |
1 u |
1 u |
|
Comparing the black
and white staplers in the end |
1 |
1 |
|
Total number of staplers at first
= 4 u + 1 u + 13
= 5 u + 13
5 u + 13 = 238
5 u = 238 - 13
5 u = 225
1 u = 225 ÷ 5 = 45
Number of staplers that he has in the end
= 1 u + 1 u
= 2 u
= 2 x 45
= 90
Answer(s): 90
