BANA 336 EXAM QUESTIONS
WITH ALL CORRECT ANSWERS
GRADED A+
A poll is to be conducted a few weeks before a state election to determine which of two
candidates running for governor has greater support. The polling organization will
randomly select 500 registered voters in the state to poll. It will record each person's
response in a variable called "Preference," with possible values of {Candidate A,
Candidate B, Other}. What is the population of interest?
RESPONSE:
The purpose of the poll is to gain knowledge about how the entire electorate (i.e., the
registered voters) in the state will vote in the election. Thus, the population is all
registered voters. Although the governor of a state represents all the citizens of the
state, the population that determines the election is a subset of all citizens, namely, the
set of all registered voters. We could be more precise, though. Not all registered voters
vote, so the *real* population is all registered voters who actually vote. - Answer-All
registered voters in the state
not the 500 registered voters
A refers to the entire collection of persons, places, objects, or events (i.e.,
"things") about that we wish to learn about - Answer-population
A fast-food company is interested in examining whether reducing the number of menu
items will increase revenue. Before rolling out the new menu nationwide, the company
wants to test it in some select markets. The company decides to examine the southwest
region first. Using the data base that contains information on the locations of all of its
franchisees' stores, the company randomly selects a collection of 50 stores. Of the 50,
half were given the new menu and half were told to continue using the old menu. Sales
from the stores in both groups were tracked for six weeks.
After analyzing the data, management concluded, with a high degree of confidence, that
using the new menu nationwide would increase revenue by an average of 20 to 30
percent, This conclusion is an example of a (an) . - Answer-
inference about a population/process
The following data on the weekly online gaming time (in hours) of a sample of college
students is as follows:
5, 11, 25, 19, 18, 20, 27, 13, 8, 10, 15, 19, 18, 9, and 12.
, Compute the sample mean to one decimal place.
x=1/n(x1+x2...xn) - Answer-15.3
A tech company is choosing to "crowd source" its start-up capital online by appealing
directly to potential customers using a popular platform. So far, there have been five
investments, which are given below (amounts are in dollars). Find the standard
deviation of the investments to two decimal places. Take all calculations toward the
answer to at least three (3) decimal places.
21 34 54 49 41
s=sqrt(21^2+34^2+54^2+49^2+41^2-5(39.8)^2)/n-1 - Answer-12.988
Your research firm has found that salaries for retail cashiers have a normal distribution
with a mean of $15,726 per year and a standard deviation of $1,388. Find the
probability that a randomly selected retail cashier has a salary greater than $16,768.
z=x-u/o
P(z>16768-15726/1388)=.75=Zscore=.7734 - Answer-not 0.7734
If Y has a normal distribution with mean 56 and standard deviation 20, find P(Y < 42).
z=x-u/o
P(z<42-56/20)=.-.7=Zscore=.2420 - Answer-0.2420
If Y has a normal distribution with mean 78 and standard deviation 18, what is P left
parenthesis 51 less or equal than Y less or equal than 60 right parenthesis ?
z=x-u/o
P(51<y<60) - Answer-0.0919
Because of slight, natural variation in the manufacturing equipment, the amount of
caffeine, Y, in Umbrella Corporation's new energy drink called "OMZ" is actually a
normally distributed random variable with a mean of 80mg and a standard deviation of
0.083 mg. What is the probability that a randomly selected can has more than 80.04 mg
of caffeine? Enter your answer as a decimal, not a percent. For example, if the answer
is 0.3161, enter 0.3161, NOT 31.61%.
z=x-u/o
P(z>80.04)
Z=80.04-80/.083
=.48193=zscore=.6844
1-.6844=.3156
(I got .3156 but the right answer is .3149) (Need to find out how to get .3149) - Answer-
.3149
If Y has a normal distribution with mean 116 and standard deviation 16, find P(Y < 87).
Enter your answer as a decimal, not a percent. For example, if the answer is 0.3161,
