MAT 142 Assignment 4 on Advertising and Sales | Montgomery County Community College

MONTGOMERY COUNTY COMMUNITY COLLEGE
MAT 142
Assignment 4
Name _____________________________
Every assignment must be typed and a sufficient amount of work shown. Graphs must
be done electronically (I do not want hand drawn graphs.) Directions for graphing using
excel are available in blackboard.
You may ask for help with the assignments.
Advertising and sales. An excellent film with a very small advertising budget must
depend largely on word-of-mouth advertising. If attendance at the film after t weeks is
given by
,
And A is in hundreds of thousands.
a. Use the quotient rule to find and simplify the numerator.
Answer
A' ( t ) = d
dt [ 400 t
t2+ 40 t+ 100 ]
¿ 400. d
dt [ t
t2 + 40t +100 ]
¿ 400
d
dt [t ] . ( t2 +40 t +100 )−t . d
dt [ t2+ 40 t+ 100 ]
( t2+ 40 t+100 )2
¿ 400
t2 + 40t +100 − 400 t (2 t+ 40)
( t2+ 40 t+100 )
2
A' ( t ) =−400(t2−100)
( t2 +40 t+ 100 )2
b. Find the rate of change in attendance for t = 5? Write a sentence
interpreting your answer. Use correct units.
Answer
mat\wh\m142\assign\assign4