A pen cost $1.50. A file cost $15.50 more than the pen. Cathy spent $140 on such pens and files. She bought twice as many pens as files.
- How many files did Cathy buy?
- How much money did Cathy spend on the pens?
|
Pens |
Files |
Total |
Number |
2 u |
1 u |
|
Value |
1.50 |
17 |
|
Total value |
3 u |
17 u |
140 |
(a)
Cost of a file
= 15.50 + 1.50
= $17
Total cost of pens and files
= 3 u + 17 u
= 20 u
20 u = 140
1 u = 140 ÷ 20 = 7
Number of files that Cathy bought
= 1 u
= 7
(b)
Amount that Cathy spent on pens
= 3 u
= 3 x 7
= $21
Answer(s): (a) 7; (b) $21