Cole had 140 more cards than David. Cole gave 20% of his cards to David. David in return gave 50% of his cards to Cole. In the end, David had 541 less cards than Cole. How many cards did Cole have at first?
| |
Cole |
David |
Comparing Cole
and Peter at first |
140 more |
|
| Before |
5 u + 140 |
5 u |
| Change 1 |
- 1 u - 28 |
+ 1 u + 28 |
| After 1 |
4 u + 112 |
6 u + 28 |
| Change 2 |
+ 3 u + 14 |
- 3 u - 14 |
| After 2 |
7 u + 126 |
3 u + 14 |
20% =
20100 =
1520% x 140
=
20100 x 140
= 28
50% x 28
=
50100 x 28
= 14
50% x 6 u
=
50100 x 6 u
= 3 u
David had 541 less cards than Cole in the end. If another 541 cards are given to David, both will have the same number of cards.
7 u + 126 = 3 u + 14 + 541
7 u - 3 u = 14 + 541 - 126
4 u = 429
1 u = 429 ÷ 4 = 39
Number of David's cards at first
= 5 u
= 5 x 39
= 195
Answer: 195
