Last week, Liam had a total of 41 purple and white pencils. Two weeks later, he sold
23 of all the purple pencils and bought another 15 white pencils. Now he has the same number of purple and white pencils. How many pencils does he have in the end?
| |
Purple |
White |
Total |
| Before |
3 u |
1 u - 15 |
4 u - 15 |
| Change |
- 2 u |
+ 15 |
|
| After |
1 u |
1 u |
|
Comparing the purple
and white pencils in the end |
1 |
1 |
|
Total number of pencils at first
= 3 u + 1 u - 15
= 4 u - 15
4 u - 15 = 41
4 u = 41 + 15
4 u = 56
1 u = 56 ÷ 4 = 14
Number of pencils that he has in the end
= 1 u + 1 u
= 2 u
= 2 x 14
= 28
Answer(s): 28
