A television manufacturer produces 600 units of a certain model each month at a cost to the manufacturer of £90 per unit and all of the produced units are sold each month. What is the minimum selling price per unit that will ensure that the monthly profit (revenue from sales minus production costs) on the sales of these units will be at least £42,000? Choose the most appropriate option:
A) £110  B) £120  C) £140  D) £160  E) £180
Explanation:   Let's say x is the amount that the manufacturer sells each unit for, then the profit per unit can be expressed as x-90. We also know that 600 units have been produced and that the total profit has to be at least £42,000.   600(x-90)≥42,000   x-90≥70   x≥160   Answer: Option £160
<result>D</result>
A television manufacturer produces 600 units of a certain model each month at a cost to the manufacturer of £90 per unit and all of the produced units are sold each month. What is the minimum selling price per unit that will ensure that the monthly profit (revenue from sales minus production costs) on the sales of these units will be at least £42,000?