Gwen spent
23 of her money on 12 files and 9 pencils. The cost of each pencil is 4 times the cost of each file. She bought some more files with
12 of her remaining money. How many files did Gwen buy altogether?
| 12 files + 9 pencils |
Remaining
amount |
Total
amount |
| 2 p = 48 u |
1 p = 24 u |
3 p |
12
files |
9
pencils |
More files |
Left |
|
| |
|
1 |
1 |
|
| 12 u |
36 u |
12 u |
|
|
Cost of 1 file = 1 u
Cost of 1 pencil = 4 u
Cost of 12 files = 12 x 1 u = 12 u
Cost of 9 pencils = 9 x 4 u = 36 u
Cost of 12 files + 9 pencils
= 12 u + 36 u
= 48 u
2 p = 48 u
1 p = 48 u ÷ 2 = 24 u
Amount of remaining money that Gwen spent on buying more files
=
12 x 24 u
= 12 u
Number of files that Gwen bought with
12 of her remaining money
= 12 u ÷ 1 u
= 12
Total number of files that Gwen bought
= 12 + 12
= 24
Answer(s): 24
