Andy had 50% more marbles than Tom. Andy gave 30% of his marbles to Tom. Tom in return gave 40% of his marbles to Andy. In the end, Tom had 684 less marbles than Andy. How many marbles did Andy have at first?
| |
Andy |
Tom |
| Before |
150% |
100% |
| Change 1 |
- 45% |
+ 45% |
| After 1 |
105% |
145% |
| Change 2 |
+ 58% |
- 58% |
| After 2 |
163% |
87% |
Number of marbles that Andy had at first in percent
= 100% + 50%
= 150%
Number of marbles that Andy gave to Tom in percent
= 30% x 150%
=
30100 x 150%
= 45%
Number of marbles that Tom gave to Andy in percent
= 40% x 145%
=
40100 x 145%
= 58%
Number of less marbles that Tom had than Andy in the end
= 163% - 87%
= 76%
76% → 684
1% → 684 ÷ 76 = 9
Number of marbles that Andy had at first
= 150%
= 150 x 9
= 1350
Answer(s): 1350
