Tim had 5 times as many yellow pens as silver pens. After giving away 6 yellow pens and buying another 18 silver pens, he had an equal number of yellow and silver pens. How many yellow pens did Tim have at first?
| |
Yellow pens |
Silver pens |
| Before |
5 u |
1 u |
| Change |
- 6 |
+ 18 |
| After |
5 u - 6 |
1 u + 18 |
The number of yellow and silver pens is the same in the end.
5 u - 6 = 1 u + 18
5 u - 1 u = 18 + 6
4 u = 6 + 18
4 u = 24
1 u = 24 ÷ 4 = 6
Number of yellow pens that Tim had at first
= 5 u
= 5 x 6
= 30
Answer(s): 30
