Xavier had 20% more marbles than Andy. Xavier gave 25% of his marbles to Andy. Andy in return gave 50% of his marbles to Xavier. In the end, Andy had 540 less marbles than Xavier. How many marbles did Xavier have at first?
| |
Xavier |
Andy |
| Before |
120% |
100% |
| Change 1 |
- 30% |
+ 30% |
| After 1 |
90% |
130% |
| Change 2 |
+ 65% |
- 65% |
| After 2 |
155% |
65% |
Number of marbles that Xavier had at first in percent
= 100% + 20%
= 120%
Number of marbles that Xavier gave to Andy in percent
= 25% x 120%
=
25100 x 120%
= 30%
Number of marbles that Andy gave to Xavier in percent
= 50% x 130%
=
50100 x 130%
= 65%
Number of less marbles that Andy had than Xavier in the end
= 155% - 65%
= 90%
90% → 540
1% → 540 ÷ 90 = 6
Number of marbles that Xavier had at first
= 120%
= 120 x 6
= 720
Answer(s): 720
