Sabrina spent
23 of her money on 12 pens and 6 files. The cost of each file is 3 times the cost of each pen. She bought some more pens with
23 of her remaining money. How many pens did Sabrina buy altogether?
12 pens + 6 files |
Remaining amount |
Total amount |
2 p = 30 u |
1 p = 15 u |
3 p |
12 pens |
6 files |
More pens |
Left |
|
|
|
2 |
1 |
|
12 u |
18 u |
10 u |
|
|
Cost of 1 pen = 1 u
Cost of 1 file = 3 u
Cost of 12 pens = 12 x 1 u = 12 u
Cost of 6 files = 6 x 3 u = 18 u
Cost of 12 pens + 6 files
= 12 u + 18 u
= 30 u
2 p = 30 u
1 p = 30 u ÷ 2 = 15 u
Amount of remaining money that Sabrina spent on buying more pens
=
23 x 15 u
= 10 u
Number of pens that Sabrina bought with
23 of her remaining money
= 10 u ÷ 1 u
= 10
Total number of pens that Sabrina bought
= 12 + 10
= 22
Answer(s): 22