• The revenue for selling ,z, units of a product: R = 40z.
,• The cost of producing ,z, units is C = 20z + 7000.
ExplanationTo obtain a profit, the revenue must be greater than the cost of producing the units. Then, we can write and solve the following inequality.
[tex]\begin{gathered} R>C \\ 40z>20z+7000 \\ \text{ Subtract 20z from both sides} \\ 40z-20z\gt20z+7000-20z \\ 200z\gt7000 \\ \text{ Divide by 200 from both sides} \\ \frac{200z}{200}\gt\frac{7000}{20} \\ z>350 \end{gathered}[/tex]AnswerTo obtain a profit, the number of units must be greater than 350.