Emily gave 15% of her collection of pens to Vanessa thereby increasing Vanessa's collection by 20%. If Emily had 51 pens left, how many pens did Vanessa have at first?
| |
Emily's pens |
Vanessa's pens |
| Before |
100% |
100 u |
| Change |
- 15% |
+ 15% = + 20 u |
| After |
85% |
120 u |
85% of Emily's collection = 51
1% of Emily's collection = 51 ÷ 85 = 0.6
15% of Emily's collection = 15 x 0.6 = 9
20 u of Vanessa's collection = 9
1 u of Vanessa's collection =
945 = 0.45
100 u of Vanessa's collection = 100 x 0.45 = 45
Answer(s): 45
