Jeremy had 3 times as many yellow pens as pink pens. After giving away 9 yellow pens and buying another 7 pink pens, he had an equal number of yellow and pink pens. How many yellow pens did Jeremy have at first?
| |
Yellow pens |
Pink pens |
| Before |
3 u |
1 u |
| Change |
- 9 |
+ 7 |
| After |
3 u - 9 |
1 u + 7 |
The number of yellow and pink pens is the same in the end.
3 u - 9 = 1 u + 7
3 u - 1 u = 7 + 9
2 u = 9 + 7
2 u = 16
1 u = 16 ÷ 2 = 8
Number of yellow pens that Jeremy had at first
= 3 u
= 3 x 8
= 24
Answer(s): 24
