Harry had 160 more cards than Tom. Harry gave 25% of his cards to Tom. Tom in return gave 60% of his cards to Harry. In the end, Tom had 646 less cards than Harry. How many cards did Harry have at first?
| |
Harry |
Tom |
Comparing Harry
and Peter at first |
160 more |
|
| Before |
4 u + 160 |
4 u |
| Change 1 |
- 1 u - 40 |
+ 1 u + 40 |
| After 1 |
3 u + 120 |
5 u + 40 |
| Change 2 |
+ 3 u + 24 |
- 3 u - 24 |
| After 2 |
6 u + 144 |
2 u + 16 |
25% =
25100 =
1425% x 160
=
25100 x 160
= 40
60% x 40
=
60100 x 40
= 24
60% x 5 u
=
60100 x 5 u
= 3 u
Tom had 646 less cards than Harry in the end. If another 646 cards are given to Tom, both will have the same number of cards.
6 u + 144 = 2 u + 16 + 646
6 u - 2 u = 16 + 646 - 144
4 u = 518
1 u = 518 ÷ 4 = 37
Number of Tom's cards at first
= 4 u
= 4 x 37
= 148
Answer: 148
