Last week, Reggie had a total of 173 pink and grey pencils. Two weeks later, he sold
45 of all the pink pencils and bought another 7 grey pencils. Now he has the same number of pink and grey pencils. How many pencils does he have in the end?
| |
Pink |
Grey |
Total |
| Before |
5 u |
1 u - 7 |
6 u - 7 |
| Change |
- 4 u |
+ 7 |
|
| After |
1 u |
1 u |
|
Comparing the pink
and grey pencils in the end |
1 |
1 |
|
Total number of pencils at first
= 5 u + 1 u - 7
= 6 u - 7
6 u - 7 = 173
6 u = 173 + 7
6 u = 180
1 u = 180 ÷ 6 = 30
Number of pencils that he has in the end
= 1 u + 1 u
= 2 u
= 2 x 30
= 60
Answer(s): 60
