Warren has 30% as many coins as Tom. If Warren gives away 50% of the coins and Tom gives away 75% of his coins, they will have 72 coins altogether. How many coins do the two of them have?
| |
Warren |
Tom |
Total |
Comparing Warren
and Tom at first |
3x2 =
6 u |
10x2 =
20 u |
|
| Before |
2x3 =
6 u |
4x5 =
20 u |
|
| Change |
- 1x3 =
- 3 u |
- 3x5 =
- 15 u |
|
| After |
1x3 =
3 u |
1x5 =
5 u |
72 |
30% =
30100 =
310 50% =
50100 =
12 75% =
75100 =
34 The number of coins that Warren has at first is repeated. Make the number of coins that Warren has the same. LCM of 3 and 2 is 6 u.
The number of coins that Tom has at first is repeated. Make the number of coins that Tom has the same. LCM of 10 and 4 is 20 u.
Number of coins in the end
= 3 u + 5 u
= 8 u
8 u = 72
1 u = 72 ÷ 8 = 9
Total number of coins that the two of them have
= 6 u + 20 u
= 26 u
= 26 x 9
= 234
Answer(s): 234
