In a stationery kiosk, 2 files and 3 staplers cost $11.50. Joseph bought 3 files and 4 staplers at $15.70 from the book shop.
- Find the cost of 1 file and 1 stapler.
- What was the cost of 1 stapler?
(a)
Let 1 file be 1 F.
Let 1 stapler be 1 S.
2 F + 3 S = 11.50 --- (1)
3 F + 4 S = 15.70 --- (2)
(2) - (1)
1 F + 1 S = 15.70 --- 11.50
1 F + 1 S = 4.20 --- (3)
Cost of 1 file and 1 stapler = $4.20
(b)
(3)
x2 2 F + 2 S = 8.40 --- (4)
(1) - (4)
1 S = 11.50 - 8.40 = $3.10
Cost of 1 stapler = $3.10
Answer(s): (a) $4.20; (b) $3.10