Roshel bought some marbles. She gave
13 of the marbles to her sister and sold
35 of the remaining marbles. After that, she bought another 22 marbles and had the same number of marbles that she bought at first. How many marbles did Roshel buy at first?
| Her sister |
Remaining marbles |
Bought marbles |
Total |
1x5 =
5 u |
2x5 =
10 u |
|
3x5 =
15 u |
| |
Sold |
Left |
|
|
| |
3x2 |
2x2 |
|
|
| 5 u |
6 u |
4 u |
22 |
|
The remaining number of marbles before Roshel bought another 22 marbles is repeated. Make the remaining number of marbles the same. LCM of 2 and 5 is 10.
Total number of marbles at first = 15 u
Number of marbles that Roshel had left and bought after that = 4 u + 22
15 u = 4 u + 22
15 u - 4 u = 22
11 u = 22
1 u = 22 ÷ 11 = 2
Total number of marbles at first
= 15 u
= 15 x 2
= 30
Answer(s): 30
