Ivory gave 15% of her collection of stamps to Tammy thereby increasing Tammy's collection by 30%. If Ivory had 51 stamps left, how many stamps did Tammy have at first?
| |
Ivory's stamps |
Tammy's stamps |
| Before |
100% |
100 u |
| Change |
- 15% |
+ 15% = + 30 u |
| After |
85% |
130 u |
85% of Ivory's collection = 51
1% of Ivory's collection = 51 ÷ 85 = 0.6
15% of Ivory's collection = 15 x 0.6 = 9
30 u of Tammy's collection = 9
1 u of Tammy's collection =
930 = 0.3
100 u of Tammy's collection = 100 x 0.3 = 30
Answer(s): 30
