Opal gave 10% of her collection of cards to Xylia thereby increasing Xylia's collection by 25%. If Opal had 45 cards left, how many cards did Xylia have at first?
| |
Opal's cards |
Xylia's cards |
| Before |
100% |
100 u |
| Change |
- 10% |
+ 10% = + 25 u |
| After |
90% |
125 u |
90% of Opal's collection = 45
1% of Opal's collection = 45 ÷ 90 = 0.5
10% of Opal's collection = 10 x 0.5 = 5
25 u of Xylia's collection = 5
1 u of Xylia's collection =
520 = 0.2
100 u of Xylia's collection = 100 x 0.2 = 20
Answer(s): 20
