Table 21.2 $\begin{array}{|l|r|r|r|r|}
\hline \text { Output (units per day) } & 0 & 10 & 20 & 30 \
\hline \text { Total cost (dollars per day) } & \$ 40 & \$ 54 & \$ 62 & \$ 80\
\hline
\end{array}$

The marginal cost per unit between 20 and 30 units of output in Table 21.2 is
A)$1.60.
B)$4.00.
C)$1.80.
D)$18.00.

Question

Table 21.2 $\begin{array}{|l|r|r|r|r|}
\hline \text { Output (units per day) } & 0 & 10 & 20 & 30 \
\hline \text { Total cost (dollars per day) } & \$ 40 & \$ 54 & \$ 62 & \$ 80\
\hline
\end{array}$

The marginal cost per unit between 20 and 30 units of output in Table 21.2 is
A)$1.60.
B)$4.00.
C)$1.80.
D)$18.00.

Quizplus · Accepted Answer

The marginal cost per unit is the change in total cost divided by the change in output. Between 20 and 30 units of output, the total cost changes by $80 - $62 = $18, and the output changes by 30 - 20 = 10 units. Therefore, the marginal cost per unit is $18 / 10 = $1.80.

Table 212 The Marginal Cost Per Unit Between 20 and 30 Units