Question
Question: A small company manufactures custom-designed mugs. The total cost (in ₹) of producing x mugs is give...
A small company manufactures custom-designed mugs. The total cost (in ₹) of producing x mugs is given by C(x)=0.1x³-3x²+50x+200
What is the marginal cost when 20 mugs are produced?

A
₹ 80
B
₹ 50
C
₹ 55
D
₹ 800
Answer
₹ 50
Explanation
Solution
The total cost function is given by C(x)=0.1x3−3x2+50x+200.
Marginal cost (MC) is the derivative of the total cost function with respect to the number of mugs produced, x.
MC=dxdC
Differentiating C(x) with respect to x:
MC=dxd(0.1x3−3x2+50x+200)
MC=0.1(3x2)−3(2x)+50(1)+0
MC=0.3x2−6x+50
To find the marginal cost when 20 mugs are produced, substitute x=20 into the marginal cost function:
MC(20)=0.3(20)2−6(20)+50
MC(20)=0.3(400)−120+50
MC(20)=120−120+50
MC(20)=50
Therefore, the marginal cost when 20 mugs are produced is ₹ 50.