Question

A manufacturer of handcrafted wine racks has determined that the cost to produce x units per month is given by C=0.3X^2+8,000. How fast is the cost per month changing when production is changing at the rate of 14 units per month and the production level is 70 UNITS?

Costs are ___ at the rate of $___ per month at this production level.

Answer 1

Costs are changing at the rate of $588 per month at this production level.

Explanation:

From the question, we have:

C = 0.3X^2 + 8,000 ........................ (1)

Differentiating equation (1) with respect to time, t, we have:

dC/dt = (0.3 * 2) X (dX/dt)....................... (2)

Where;

X = 70

dX/dt = 14

Substituting this into equation (2), we have:

dC/dt = (0.3 * 2) * 70 * 14

dC/dt = 588

This implies that costs are changing at the rate of $588 per month at this production level.