Statistics Homework
In 2011, there were 150 participants in a quiz competition. In 2012, there were 185 participants in this quiz competition.
Select the true statement about participants in the quiz competition from 2011 to 2012. Percentages are rounded to the nearest tenths place.
a.)
The absolute change is 35 students and the relative change indicates an increase of 18.92%.
b.)
The absolute change is -35 students and the relative change indicates a decrease of 35%.
c.)
The absolute change is 35 students and the relative change indicates an increase of 23.3%.
d.)
The absolute change is -35 students and the relative change indicates a decrease of 23.3%.
A companys market share went from 50 to 40 percent of the total market.
Of the following choices, which two statements about the company’s market shares are true?
a.)
There was a 20% decrease in market shares.
b.)
Market shares dropped by 25 percentage points.
c.)
Market shares dropped by 20 percentage points.
d.)
There was a 10% decrease in market shares.
e.)
There was a 25% decrease in market shares.
f.)
Market shares dropped by 10 percentage points.
The following are the Consumer Price Index (CPI) for the years 1991-1993. All of the values use a reference year of 1986.
Year
CPI
1991
110
1992
120
1993
135
Whichof the following is true about the CPI, based on the information?
a.)
$100 in 1992 would have been worth $100 in 1986.
b.)
$100 in 1986 would be equivalent to $135 in 1993.
c.)
$100 in 1993 would be equivalent to $120 in 1992.
d.)
$100 in 1991 would have been worth $110 in 1986.
How about members of a local professional sports team who are conducting a survey?
Which data collection method would provide biased results for the question “What is your favorite sport?”
a.)
Ask people attending a soccer game.
b.)
Ask people walking on the beach.
c.)
Ask people attending a concert.
d.)
Ask people at a shopping mall.
Kendra thinks it’s important to know how much money her customers make, so she can decide whether to offer high-end items. Because Kendras shop is in a small town, most of her customers are her friends and neighbors. One survey question asks, How much money do you make each month?
A customer who responds by writing down a really high number to impress Kendra is an example of ______ bias.
a.)
selection
b.)
unintentional
c.)
response
d.)
non-response
A survey asked the following question: Do you agree that drinking is okay as long as you are of the legal age and that you don’t get drunk?
What type of bias does this question introduce?
a.)
Response
b.)
Non-response
c.)
Deliberate
d.)
Selection
Select the example that representsconveniencesampling.
a.)
George asks every 10th customer to fill out a survey.
b.)
George offers a free cookie to anyone who agrees to answer the survey questions.
c.)
George asks the same survey question to the first 20 customers to visit the food truck.
d.)
George hangs flyers for volunteers to answer questions for the survey on various streets and convenience stores throughout the city.
Which statement about systematic errors is FALSE?
a.)
They arise due to errors in the measuring instruments used.
b.)
They arise from the design of the study.
c.)
They are reproducible inaccuracies that are consistently in the same direction.
d.)
They can be eliminated by repeating observations or increasing the sample size.
After all of the surveys have been compiled and analyzed, the calculated level of satisfaction for handset selection for a sample was 6.5 0.3.
Select the true statement for this scenario.
a.)
The estimate is equal to 6.5 and the margin of error is equal to 0.3.
b.)
The margin of error is equal to 6.5 and the estimate is equal to 0.3.
c.)
The margin of error is equal to 0.3 and the confidence interval is equal to 6.5.
d.)
The estimate is equal to 6.5 and the confidence interval is equal to 0.3.
Which of these is NOT a possible outcome?
a.)
Flipping tails on a coin
b.)
Rolling a prime number that is larger than 5 on a die
c.)
Drawing a Queen of Hearts from a standard deck of cards
d.)
Rolling an odd number that is less than 2 on a die
A game involves a spinner that is evenly separated into four sections, as well an eight-sided die. To play the game, each player spins the spinner once and rolls the die once.
What is the number of individual outcomes from spinning and rolling one time?
a.)
4
b.)
12
c.)
32
d.)
8
The theoretical probability of an event is the number of desired outcomes divided by all possible outcomes.
What is the probability of drawing an ace from a shuffled standard deck of playing cards?
a.)
b.)
c.)
d.)
A box has 10 disks numbered 1 through 10. A disk is drawn at random 50 times with replacement. The disk numbered 7 was drawn 6 times.
What is the relative frequency of getting the disk numbered 7 on the next draw?
a.)
b.)
c.)
d.)
Which of the following is true of BOTH discrete and continuous probability distributions?
a.)
The probability of each outcome is 1.
b.)
The sum of all probabilities lies between 0 to 1.
c.)
The sum of all probabilities is less than or equal to 1.
d.)
The sum of all probabilities is equal to 1.
A spinner is divided into four equal areas and colored red, green, yellow, and blue.
Which statement is most likely to be true?
a.)
The probability of the spinner landing on the green region is equal to 0.25 when the number of trials is less than 25.
b.)
The probability of the spinner landing on the green region is close to 0.25 when the number of trials is more than 250.
c.)
The probability of the spinner landing on the green region is close to 0.25 when the number of trials is less than 25.
d.)
The probability of the spinner landing on the green region is close to 0.25 when the number of trials is less than 250.
Which of the following statements is true?
a.)
The Monte Carlo method is another name for simulations of probability.
b.)
Repeating trials of chance will enable you to achieve theoretical certainty.
c.)
All statements are true.
d.)
Sample sizes of 15 or less are generally representative in simulations.
Sarah plays a game in which she can purchase a ticket. Each ticket has several chances, or “catches,” to win money.
The table below shows the probability of winning at each stage, and how much money the ticket can win at each catch. Every time Sarah plays the game, her ticket is played through each catch, which means she can win money at each stage.
Catch
Probability
Winnings
Catch 0
50%
$1
Catch 1
30%
$5
Catch 2
15%
$10
Catch 3
5%
$100
Given the probabilities and payout values in this table, what is the expected value of Sarah’s ticket?
a.)
$6.70
b.)
$116.00
c.)
$53.50
d.)
$8.50
In a well-shuffled pack of cards, the odds in favor of picking a diamond card are.
What is the probability of drawing this card?
a.)
b.)
c.)
d.)
