Practice Test #3
Directions:
Use this practice test as a guide for your study for Test #3. This exam is
not
comprehensive, so study your class notes and homework problems in addition to completing this
exam. Solutions are posted on the course website unde
r “Solutions”.
Directions:
Show all work for full credit. Correct answers without work shown to support the
answer will be awarded 0 points. Partial credit will be given where appropriate.
1)
The revenue function of a company is
10
4000
)
(
2
x
x
x
R
, where x is the number of units
produced and sold.
a)
Find the revenue for 20 units and for 21 units and the difference of revenues.
R(20) = _______________
R(21) = _______________
R(21)
–
R(20) = _____________
b)
Find the marginal revenue R’(x) and R’(20).
R
’(x) = _______________
R’(20) = ____________
c)
What does R’(20) mean in terms of the situation?
d) Which is more accurate? R’(20) or R(21) –
R(20)
(circle one)
Why?
2)
The cost function for a company is
x
x
C
4
400
)
(
and the revenue function is
2
100
)
(
x
x
x
R
, where x is the number of units produced and sold.
Find the breakeven
point(s). (Remember, a breakeven point is an ordered pair!)
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
This is the end of the preview.
Sign up
to
access the rest of the document.
 Spring '10
 Staff
 Calculus, Addition, Derivative, open intervals

Click to edit the document details