Abi bought some coins. She gave
17 of the coins to her sister and sold
25 of the remaining coins. After that, she bought another 204 coins and had the same number of coins that she bought at first. How many coins did Abi buy at first?
| Her sister |
Remaining coins |
Bought coins |
Total |
1x5 =
5 u |
6x5 =
30 u |
|
7x5 =
35 u |
| |
Sold |
Left |
|
|
| |
2x6 |
3x6 |
|
|
| 5 u |
12 u |
18 u |
204 |
|
The remaining number of coins before Abi bought another 204 coins is repeated. Make the remaining number of coins the same. LCM of 6 and 5 is 30.
Total number of coins at first = 35 u
Number of coins that Abi had left and bought after that = 18 u + 204
35 u = 18 u + 204
35 u - 18 u = 204
17 u = 204
1 u = 204 ÷ 17 = 12
Total number of coins at first
= 35 u
= 35 x 12
= 420
Answer(s): 420
