Zoe spent
34 of her money on 10 files and 7 pencils. The cost of each pencil is 2 times the cost of each file. She bought some more files with
12 of her remaining money. How many files did Zoe buy altogether?
| 10 files + 7 pencils |
Remaining
amount |
Total
amount |
| 3 p = 24 u |
1 p = 8 u |
4 p |
10
files |
7
pencils |
More files |
Left |
|
| |
|
1 |
1 |
|
| 10 u |
14 u |
4 u |
|
|
Cost of 1 file = 1 u
Cost of 1 pencil = 2 u
Cost of 10 files = 10 x 1 u = 10 u
Cost of 7 pencils = 7 x 2 u = 14 u
Cost of 10 files + 7 pencils
= 10 u + 14 u
= 24 u
3 p = 24 u
1 p = 24 u ÷ 3 = 8 u
Amount of remaining money that Zoe spent on buying more files
=
12 x 8 u
= 4 u
Number of files that Zoe bought with
12 of her remaining money
= 4 u ÷ 1 u
= 4
Total number of files that Zoe bought
= 10 + 4
= 14
Answer(s): 14
