Xandra spent
45 of her money on 12 files and 8 pencils. The cost of each pencil is 3 times the cost of each file. She bought some more files with
23 of her remaining money. How many files did Xandra buy altogether?
| 12 files + 8 pencils |
Remaining
amount |
Total
amount |
| 4 p = 36 u |
1 p = 9 u |
5 p |
12
files |
8
pencils |
More files |
Left |
|
| |
|
2 |
1 |
|
| 12 u |
24 u |
6 u |
|
|
Cost of 1 file = 1 u
Cost of 1 pencil = 3 u
Cost of 12 files = 12 x 1 u = 12 u
Cost of 8 pencils = 8 x 3 u = 24 u
Cost of 12 files + 8 pencils
= 12 u + 24 u
= 36 u
4 p = 36 u
1 p = 36 u ÷ 4 = 9 u
Amount of remaining money that Xandra spent on buying more files
=
23 x 9 u
= 6 u
Number of files that Xandra bought with
23 of her remaining money
= 6 u ÷ 1 u
= 6
Total number of files that Xandra bought
= 12 + 6
= 18
Answer(s): 18
