The cost and revenue functions of a product are given by C(x) = 20 x + 4000 and R(x) = 60x + 2000, respectively, where x is the number of items produced and sold. How many items must be sold to realise some profit?
We have, profit = Revenue – Cost
= (60x + 2000) – (20x + 4000)
= 40x – 2000
To earn some profit, 40x – 2000 > 0
⇒ x > 50
Hence, the manufacturer must sell more than 50 items to realise some profit.