Ryan had 5 times as many blue pencils as silver pencils. After giving away 4 blue pencils and buying another 4 silver pencils, he had an equal number of blue and silver pencils. How many blue pencils did Ryan have at first?
| |
Blue pencils |
Silver pencils |
| Before |
5 u |
1 u |
| Change |
- 4 |
+ 4 |
| After |
5 u - 4 |
1 u + 4 |
The number of blue and silver pencils is the same in the end.
5 u - 4 = 1 u + 4
5 u - 1 u = 4 + 4
4 u = 4 + 4
4 u = 8
1 u = 8 ÷ 4 = 2
Number of blue pencils that Ryan had at first
= 5 u
= 5 x 2
= 10
Answer(s): 10
