Roshel bought some coins. She gave
15 of the coins to her sister and sold
35 of the remaining coins. After that, she bought another 170 coins and had the same number of coins that she bought at first. How many coins did Roshel buy at first?
| Her sister |
Remaining coins |
Bought coins |
Total |
1x5 =
5 u |
4x5 =
20 u |
|
5x5 =
25 u |
| |
Sold |
Left |
|
|
| |
3x4 |
2x4 |
|
|
| 5 u |
12 u |
8 u |
170 |
|
The remaining number of coins before Roshel bought another 170 coins is repeated. Make the remaining number of coins the same. LCM of 4 and 5 is 20.
Total number of coins at first = 25 u
Number of coins that Roshel had left and bought after that = 8 u + 170
25 u = 8 u + 170
25 u - 8 u = 170
17 u = 170
1 u = 170 ÷ 17 = 10
Total number of coins at first
= 25 u
= 25 x 10
= 250
Answer(s): 250
