Shiyun spent
38 of her money on 10 markers and 4 folders. The cost of one folder was twice the cost of one marker. She bought some more folders with
13 of her remaining money. How many folders did Shiyun buy altogether?
10 markers and
4 folders |
Remaining amount |
| 3x3 |
5x3 |
| |
More folders |
Left |
| |
1x5 |
2x5 |
| 9 p |
5 p |
10 p |
Cost of 1 marker = 1 u
Cost of 1 folder = 2 u
Cost of 10 markers = 10 x 1 u = 10 u
Cost of 4 folders = 4 x 2 u = 8 u
Total cost of 10 markers and 4 folders
= 10 u + 8 u
= 18 u
9 p = 18 u
1 p = 18 ÷ 9 = 2 u
Amount that Shiyun used to buy more folders
= 5 p
= 5 x 2 u
= 10 u
Number of more folders that Shiyun bought
= 10 u ÷ 2 u
= 5
Total number of folders that Shiyun bought
= 4 + 5
= 9
Answer(s): 9
