Harry had 20% more balls than Mark. Harry gave 10% of his balls to Mark. Mark in return gave 50% of his balls to Harry. In the end, Mark had 972 less balls than Harry. How many balls did Harry have at first?
| |
Harry |
Mark |
| Before |
120% |
100% |
| Change 1 |
- 12% |
+ 12% |
| After 1 |
108% |
112% |
| Change 2 |
+ 56% |
- 56% |
| After 2 |
164% |
56% |
Number of balls that Harry had at first in percent
= 100% + 20%
= 120%
Number of balls that Harry gave to Mark in percent
= 10% x 120%
=
10100 x 120%
= 12%
Number of balls that Mark gave to Harry in percent
= 50% x 112%
=
50100 x 112%
= 56%
Number of less balls that Mark had than Harry in the end
= 164% - 56%
= 108%
108% → 972
1% → 972 ÷ 108 = 9
Number of balls that Harry had at first
= 120%
= 120 x 9
= 1080
Answer(s): 1080
