In a bookstore, 4 pens and 5 markers cost $18.60. Joseph bought 5 pens and 6 markers at $22.70 from the book shop.
- Find the cost of 1 pen and 1 marker.
- What was the cost of 1 marker?
(a)
Let 1 pen be 1 P.
Let 1 marker be 1 M.
4 P + 5 M = 18.60 --- (1)
5 P + 6 M = 22.70 --- (2)
(2) - (1)
1 P + 1 M = 22.70 --- 18.60
1 P + 1 M = 4.10 --- (3)
Cost of 1 pen and 1 marker = $4.10
(b)
(3)
x4 4 P + 4 M = 16.40 --- (4)
(1) - (4)
1 M = 18.60 - 16.40 = $2.20
Cost of 1 marker = $2.20
Answer(s): (a) $4.10; (b) $2.20