Last week, Ahmad had a total of 307 brown and yellow pens. Two weeks later, he sold
56 of all the brown pens and bought another 15 yellow pens. Now he has the same number of brown and yellow pens. How many pens does he have in the end?
| |
Brown |
Yellow |
Total |
| Before |
6 u |
1 u - 15 |
7 u - 15 |
| Change |
- 5 u |
+ 15 |
|
| After |
1 u |
1 u |
|
Comparing the brown
and yellow pens in the end |
1 |
1 |
|
Total number of pens at first
= 6 u + 1 u - 15
= 7 u - 15
7 u - 15 = 307
7 u = 307 + 15
7 u = 322
1 u = 322 ÷ 7 = 46
Number of pens that he has in the end
= 1 u + 1 u
= 2 u
= 2 x 46
= 92
Answer(s): 92
