Page 1 of 136
WGU - C957 APPLIED ALGEBRA OA
ACTUAL EXAM QUESTIONS AND
CORRECT DETAILED ANSWERS LATEST
EXAM UPDATE
The value, V, of your college savings account with a deposit amount of
$500 and 8% simple annual interest can be calculated using the formula:
V=500+500(.08)t
, where t is years. After 1 year, your account has $540 and after 5 years,
your account has $700.
What is the average rate of change in your savings account (round to the
nearest dollar)?
$36 per year
$40 per year
-$36 per year
-$40 per year - ✔✔✔ Correct Answer > Correct! Your savings account
increases on average by $40 a year.
700-540/5-1=40
,Page 2 of 136
On a recent trip, your friend Kyle drove 130 miles in 2 hours. He tells
you he drove about 65 miles per hour for most of the trip but did speed
up to 70 miles per hour at one point while he was passing someone.
Which of Kyle's speeds (the 65 mph or the 70 mph) represents an
average rate of change? - ✔✔✔ Correct Answer > 130/2=65
The average rate of change is 65 mph. It is the speed that Kyle averaged
for his 2-hour trip. It is also the average rate of change because it covers
a pretty large interval of time.
On a recent trip, your friend Kyle drove 130 miles in 2 hours. He tells
you he drove about 65 miles per hour for most of the trip but did speed
up to 70 miles per hour at one point just while he was passing someone.
Which of Kyle's speeds (the 65 mph or the 70 mph) represents an
instantaneous rate of change? - ✔✔✔ Correct Answer > The instantaneous
rate of change is 70 mph. This is because it is the speed that Kyle
momentarily sped up to pass someone. This is also the instantaneous rate
of change because it covers a pretty small interval of time with respect
to his 2-hour trip (he was only going 70 mph for a few "instants" of his
trip).
,Page 3 of 136
Stella sells drinks at her sandwich shop. Stella estimates her revenue
from drinks alone, R, to be dependent on the price she sets for the
drinks, x. Stella had a regression calculated based on some data and has
the following regression function: R(x)=12x-x^2
. Find the average rate of change between the points (1, 11) and (4, 32).
9
6
5
7 - ✔✔✔ Correct Answer > Correct! The average rate of change between the
points is 7 since
m=change in ychange in x=(11−32)/(1−4)=(−21)/(−3)=7
.
The number of memberships at Sunrise Sky Spa since 2000 can be
modeled by the function m(t)=0.6t4−20t3+200t2−500t+1000
,
, Page 4 of 136
where t is the number of years since 2000. Calculate the number of
memberships on October 1, 2005.
There were approximately 1,693 memberships on October 1, 2005.
There were approximately 903 memberships on October 1, 2005.
There were approximately 1,592 memberships on October 1, 2005.
There were approximately 1,221 memberships on October 1, 2005.
- ✔✔✔ Correct Answer > There were approximately 1,592 memberships on
October 1, 2005.
Correct! Substitute t = 5.75 into m(t)
, and you have
m(5.75)=0.6(5.75)4−20(5.75)3+200(5.75)2−500(5.75)+1000≈0.6(109
3.13)−20(190.11)+200(33.06)−2875+1000≈655.88−3802.2+6612
The average rate of change for a given stock from x = 3 to x = 7 is
−$0.595.
What does this mean?
It means that every hour, the value of the stock dropped by an average of
$0.60.
WGU - C957 APPLIED ALGEBRA OA
ACTUAL EXAM QUESTIONS AND
CORRECT DETAILED ANSWERS LATEST
EXAM UPDATE
The value, V, of your college savings account with a deposit amount of
$500 and 8% simple annual interest can be calculated using the formula:
V=500+500(.08)t
, where t is years. After 1 year, your account has $540 and after 5 years,
your account has $700.
What is the average rate of change in your savings account (round to the
nearest dollar)?
$36 per year
$40 per year
-$36 per year
-$40 per year - ✔✔✔ Correct Answer > Correct! Your savings account
increases on average by $40 a year.
700-540/5-1=40
,Page 2 of 136
On a recent trip, your friend Kyle drove 130 miles in 2 hours. He tells
you he drove about 65 miles per hour for most of the trip but did speed
up to 70 miles per hour at one point while he was passing someone.
Which of Kyle's speeds (the 65 mph or the 70 mph) represents an
average rate of change? - ✔✔✔ Correct Answer > 130/2=65
The average rate of change is 65 mph. It is the speed that Kyle averaged
for his 2-hour trip. It is also the average rate of change because it covers
a pretty large interval of time.
On a recent trip, your friend Kyle drove 130 miles in 2 hours. He tells
you he drove about 65 miles per hour for most of the trip but did speed
up to 70 miles per hour at one point just while he was passing someone.
Which of Kyle's speeds (the 65 mph or the 70 mph) represents an
instantaneous rate of change? - ✔✔✔ Correct Answer > The instantaneous
rate of change is 70 mph. This is because it is the speed that Kyle
momentarily sped up to pass someone. This is also the instantaneous rate
of change because it covers a pretty small interval of time with respect
to his 2-hour trip (he was only going 70 mph for a few "instants" of his
trip).
,Page 3 of 136
Stella sells drinks at her sandwich shop. Stella estimates her revenue
from drinks alone, R, to be dependent on the price she sets for the
drinks, x. Stella had a regression calculated based on some data and has
the following regression function: R(x)=12x-x^2
. Find the average rate of change between the points (1, 11) and (4, 32).
9
6
5
7 - ✔✔✔ Correct Answer > Correct! The average rate of change between the
points is 7 since
m=change in ychange in x=(11−32)/(1−4)=(−21)/(−3)=7
.
The number of memberships at Sunrise Sky Spa since 2000 can be
modeled by the function m(t)=0.6t4−20t3+200t2−500t+1000
,
, Page 4 of 136
where t is the number of years since 2000. Calculate the number of
memberships on October 1, 2005.
There were approximately 1,693 memberships on October 1, 2005.
There were approximately 903 memberships on October 1, 2005.
There were approximately 1,592 memberships on October 1, 2005.
There were approximately 1,221 memberships on October 1, 2005.
- ✔✔✔ Correct Answer > There were approximately 1,592 memberships on
October 1, 2005.
Correct! Substitute t = 5.75 into m(t)
, and you have
m(5.75)=0.6(5.75)4−20(5.75)3+200(5.75)2−500(5.75)+1000≈0.6(109
3.13)−20(190.11)+200(33.06)−2875+1000≈655.88−3802.2+6612
The average rate of change for a given stock from x = 3 to x = 7 is
−$0.595.
What does this mean?
It means that every hour, the value of the stock dropped by an average of
$0.60.
