Julie had 128 pencils.
34 of them were silver pencils and the rest were brown pencils. After she had given away some silver pencils, the ratio of the number of silver pencils to the number of brown pencils became 3 : 4. How many silver pencils did she give away?
| |
Silver |
Brown |
Total |
| Before |
3x4 =
12 u |
1x4 =
4 u |
4x4 =
16 u |
| Change |
- 9 u |
|
|
| After |
3 u |
4 u |
7 u |
The number of brown pencils remained unchanged.
LCM of 1 and 4 = 4
Total number of pencils at first = 16 u
16 u = 128
1 u = 128 ÷ 16 = 8
Number of silver pencils that she gave away
= 12 u - 3 u
= 9 u
= 9 x 8
= 72
Answer(s):72
