BUSINESS DATA ANALYTICS BDAN 310
FINAL EXAM PREP
A __________ describes the range and relative likelihood of all possible values for a random
variable. - ANS-probability distribution for a random variable
In the probability table below, which value is a marginal probability?
Completed
Obstacle Course Level No Yes Total
Challenging 0.4 0.3 0.7
Easy 0.1 0.2 0.3
Total 0.5 0.5 1.0 - ANS-0.5
Bayes' theorem is a method used to compute __________ probabilities. - ANS-Posterior
A health conscious student faithfully wears a device that tracks his steps. Suppose that the
distribution of the number of steps he takes is normally distributed with a mean of 10,000 and
a standard deviation of 1,500 steps. How many steps would he have to take to make the cut for
the top 5% for his distribution? - ANS-12,467
A health conscious student faithfully wears a device that tracks his steps. Suppose that the
distribution of the number of steps he takes in a day is normally distributed with a mean of
10,000 and a standard deviation of 1,500 steps. One day he took 15,000 steps. What was his
percentile on that day? - ANS-99.7%
Fast food restaurants pride themselves in being able to fill orders quickly. A study was done at a local
fast food restaurant to determine how long it took customers to receive their order at the drive-thru. It
was discovered that the time it takes for orders to be filled is exponentially distributed with a mean of
1.5 minutes. What is the probability that it takes less than one minute to fill an order? - ANS-.4866
A variable that can only take on specific numeric values is called a - ANS-Discrete random variable
A joint probability is the - ANS-probability of the intersection of two events.
Two events are independent if - ANS-P(A | B) = P(A) or P(B | A) = P(B)
The newest model of smart car is supposed to get excellent gas mileage. A thorough study
showed that gas mileage (measured in miles per gallon) is normally distributed with a mean of
75 miles per gallon and a standard deviation of 10 miles per gallon. What is the probability
, that, if driven normally, the car will get 100 miles per gallon or better? - ANS-.6%
What is the mean of x, given the exponential probability function f(x) = 1/20e^(x/20) for x >= 0? - ANS-20
Probability is the - ANS-numerical measure of the likelihood that an event will occur.
All the events in the sample space that are not part of the specified event are called - ANS-The
complement of the event
The center of a normal curve is - ANS-the mean of the distribution.
The event containing the outcomes belonging to A or B or both is the __________ of A and B. - ANS-
Union
The __________ probability distribution can be used to estimate the number of vehicles that
go through an intersection during the lunch hour. - ANS-Poisson
What is the total area under the normal distribution curve? - ANS-1
Which of the following is not a characteristic of the normal probability distribution?
The distribution is symmetrical.
The mean of the distribution can be negative, zero, or positive.
The standard deviation must be 1
.
The mean, median, and the mode are equal. - ANS-The standard deviation must be 1
The random variable X is known to be uniformly distributed between 2 and 12. Compute E(X),
the expected value of the distribution. - ANS-7
A survey of 100 random high school students finds that 85 students watched the Super Bowl, 25
students watched the Stanley Cup Finals, and 20 students watched both games. How many
students did not watch either game? - ANS-10
The number of minutes that Samantha waits to catch the bus is uniformly distributed between
0 and 15 minutes. What is the probability that Samantha has to wait less than 4.5 minutes to
catch the bus? - ANS-30%
(4.5 - 0) / (15 - 0) = .3 or 30%
All of the following are examples of discrete random variables except
Marital status
Number of tickets sold
FINAL EXAM PREP
A __________ describes the range and relative likelihood of all possible values for a random
variable. - ANS-probability distribution for a random variable
In the probability table below, which value is a marginal probability?
Completed
Obstacle Course Level No Yes Total
Challenging 0.4 0.3 0.7
Easy 0.1 0.2 0.3
Total 0.5 0.5 1.0 - ANS-0.5
Bayes' theorem is a method used to compute __________ probabilities. - ANS-Posterior
A health conscious student faithfully wears a device that tracks his steps. Suppose that the
distribution of the number of steps he takes is normally distributed with a mean of 10,000 and
a standard deviation of 1,500 steps. How many steps would he have to take to make the cut for
the top 5% for his distribution? - ANS-12,467
A health conscious student faithfully wears a device that tracks his steps. Suppose that the
distribution of the number of steps he takes in a day is normally distributed with a mean of
10,000 and a standard deviation of 1,500 steps. One day he took 15,000 steps. What was his
percentile on that day? - ANS-99.7%
Fast food restaurants pride themselves in being able to fill orders quickly. A study was done at a local
fast food restaurant to determine how long it took customers to receive their order at the drive-thru. It
was discovered that the time it takes for orders to be filled is exponentially distributed with a mean of
1.5 minutes. What is the probability that it takes less than one minute to fill an order? - ANS-.4866
A variable that can only take on specific numeric values is called a - ANS-Discrete random variable
A joint probability is the - ANS-probability of the intersection of two events.
Two events are independent if - ANS-P(A | B) = P(A) or P(B | A) = P(B)
The newest model of smart car is supposed to get excellent gas mileage. A thorough study
showed that gas mileage (measured in miles per gallon) is normally distributed with a mean of
75 miles per gallon and a standard deviation of 10 miles per gallon. What is the probability
, that, if driven normally, the car will get 100 miles per gallon or better? - ANS-.6%
What is the mean of x, given the exponential probability function f(x) = 1/20e^(x/20) for x >= 0? - ANS-20
Probability is the - ANS-numerical measure of the likelihood that an event will occur.
All the events in the sample space that are not part of the specified event are called - ANS-The
complement of the event
The center of a normal curve is - ANS-the mean of the distribution.
The event containing the outcomes belonging to A or B or both is the __________ of A and B. - ANS-
Union
The __________ probability distribution can be used to estimate the number of vehicles that
go through an intersection during the lunch hour. - ANS-Poisson
What is the total area under the normal distribution curve? - ANS-1
Which of the following is not a characteristic of the normal probability distribution?
The distribution is symmetrical.
The mean of the distribution can be negative, zero, or positive.
The standard deviation must be 1
.
The mean, median, and the mode are equal. - ANS-The standard deviation must be 1
The random variable X is known to be uniformly distributed between 2 and 12. Compute E(X),
the expected value of the distribution. - ANS-7
A survey of 100 random high school students finds that 85 students watched the Super Bowl, 25
students watched the Stanley Cup Finals, and 20 students watched both games. How many
students did not watch either game? - ANS-10
The number of minutes that Samantha waits to catch the bus is uniformly distributed between
0 and 15 minutes. What is the probability that Samantha has to wait less than 4.5 minutes to
catch the bus? - ANS-30%
(4.5 - 0) / (15 - 0) = .3 or 30%
All of the following are examples of discrete random variables except
Marital status
Number of tickets sold
