Question 1

Let z be a normal random variable with mean 0 and standard deviation 1.What is P(z < -2.1)?

Accepted Answer

A) 0.4821 
B) -0.4821 
C) 0.9821 
D) 0.0179 
E) -0.0179 
A) 0.4821 
B) -0.4821 
C) 0.9821 
D) 0.0179 
E) -0.0179

Question 2

The area to the left of the mean in any normal distribution is equal to _______.

Accepted Answer

A) the mean 
B) 1 
C) the variance 
D) 0.5 
E) -0.5 
A) the mean 
B) 1 
C) the variance 
D) 0.5 
E) -0.5

Question 3

Since a normal distribution curve extends from minus infinity to plus infinity, the area under the curve is infinity.

Accepted Answer

A) True 
 B)False

Question 4

Participants in a 2 day biking event, cross the finish line at a rate of 10 bike riders per fifteen minute interval.The probability that less than 10 minutes will elapse between car arrivals is _____________.

Accepted Answer

A) .0001 
B) .9987 
C) .0013 
D) .6667 
E) .1667 
A) .0001 
B) .9987 
C) .0013 
D) .6667 
E) .1667

Question 5

For the normal approximation to be a good approximation for binomial distribution, n*p must be greater than ___________.

Accepted Answer

A) 50 
B) 5 
C) 0.5 
D) 0.05 
E) 0 
A) 50 
B) 5 
C) 0.5 
D) 0.05 
E) 0

Question 6

If x, the time (in minutes)to complete an change job at certain auto service station, is uniformly distributed over the interval 20 to 30, inclusively (20 $\le$ x $\le$ 30), then the probability that an oil change job is completed in 21.75 to 24.25 minutes, inclusively, i.e., P(21.75$\le$ x $\le$24.25)is __________________.

Accepted Answer

A) 0.250 
B) 0.333 
C) 0.375 
D) 0.000 
E) 1.000 
A) 0.250 
B) 0.333 
C) 0.375 
D) 0.000 
E) 1.000

Question 7

The height of the rectangle depicting a uniform distribution is the probability of each outcome and it is the same for all of the possible outcomes

Accepted Answer

A) True 
 B)False

Question 8

If x is uniformly distributed over the interval 8 to 12, inclusively (8 $\le$ x $\le$ 12), then the probability, P(13 $\le$ x $\le$15), is __________________.

Accepted Answer

A) 0.250 
B) 0.500 
C) 0.375 
D) 0.000 
E) 1.000 
A) 0.250 
B) 0.500 
C) 0.375 
D) 0.000 
E) 1.000

Question 9

The probability that someone will prefer Coke over Pepsi is 0.56.A researcher asked 90 people which soda pop they preferred, and used the normal approximation to the binomial with a correction for continuity, what would be the probability at least 50 preferring Coke?

Accepted Answer

A) 0.615 
B) 0.507 
C) 0.560 
D) 0.900 
E) 0.576 
A) 0.615 
B) 0.507 
C) 0.560 
D) 0.900 
E) 0.576

Question 10

Within a range of z scores from -1 to +1, you can expect to find _______ per cent of the values in a normal distribution.

Accepted Answer

A) 95 
B) 99 
C) 68 
D) 34 
E) 100 
A) 95 
B) 99 
C) 68 
D) 34 
E) 100

Question 11

Suppose you are working with a data set that is normally distributed with a mean of 400 and a standard deviation of 20.Determine the most likely value of x such that 60% of the values are greater than x.

Accepted Answer

A) 404.5 
B) 395.5 
C) 405.0 
D) 395.0 
E) 415.0 
A) 404.5 
B) 395.5 
C) 405.0 
D) 395.0 
E) 415.0

Question 12

Binomial distributions in which the sample sizes are large may be approximated by a Poisson distribution.

Accepted Answer

A) True 
 B)False

Question 13

The expected (mean)life of a particular type of light bulb is 1,000 hours with a standard deviation of 50 hours.The life of this bulb is normally distributed.Which most closely reflects the probability that a randomly selected bulb would last fewer than 940 hours?

Accepted Answer

A) 0.3849 
B) 0.8849 
C) 0.1151 
D) 0.6151 
E) 0.6563 
A) 0.3849 
B) 0.8849 
C) 0.1151 
D) 0.6151 
E) 0.6563

Question 14

A recent market study has determined that the probability that a young adult would be willing to try a new online financial service that your company is offering is 50%.In a random sample of 10 young adults, the approximate probability that at least 2 but no more than 3 will be willing to try this new service is _________.

Accepted Answer

A) 0.1575 
B) 0.1612 
C) 0.1775 
D) 0.1812 
E) 0.1975 
A) 0.1575 
B) 0.1612 
C) 0.1775 
D) 0.1812 
E) 0.1975

Question 15

The standard normal distribution is also called a finite distribution because its mean is zero and standard deviation one, always.

Accepted Answer

A) True 
 B)False

Question 16

Suppose the total time to fill a routine prescription at a local pharmacy averages 35 minutes starting from the time the physician places the order to the time it is dispensed.Assume the standard deviation is 11 minutes.The z-score for x = 46 is ________.

Accepted Answer

A) 1.0 
B) -1.0 
C) 11 
D) -11 
E) .10 
A) 1.0 
B) -1.0 
C) 11 
D) -11 
E) .10

Question 17

Let z be a normal random variable with mean 0 and standard deviation 1.Which of these most closely reflects P(-2.25 < z < -1.1)?

Accepted Answer

A) 0.3643 
B) 0.8643 
C) 0.1235 
D) 0.4878 
E) 0.5000 
A) 0.3643 
B) 0.8643 
C) 0.1235 
D) 0.4878 
E) 0.5000

Question 18

Let z be a normal random variable with mean 0 and standard deviation 1.The 50th percentile of z is most closely reflected by ____________.

Accepted Answer

A) 0.6700 
B) -1.254 
C) 0.0000 
D) 1.2800 
E) 0.5000 
A) 0.6700 
B) -1.254 
C) 0.0000 
D) 1.2800 
E) 0.5000

Question 19

In a busy gas station, an average of 2.4 cars arrive every minute.What is the average time between arrivals?

Accepted Answer

A) 0.42 minutes 
B) 2.08 minutes 
C) 5.24 minutes 
D) 2.40 minutes 
E) 5.00 minutes 
A) 0.42 minutes 
B) 2.08 minutes 
C) 5.24 minutes 
D) 2.40 minutes 
E) 5.00 minutes

Question 20

The net profit from a certain investment is normally distributed with a mean of $2,500 and a standard deviation of $1,000.The probability that the investor will not have a net loss is _____________.

Accepted Answer

A) 0.4938 
B) 0.0062 
C) 0.9938 
D) 0.5062 
E) 0.0000 
A) 0.4938 
B) 0.0062 
C) 0.9938 
D) 0.5062 
E) 0.0000

Let z be a normal random variable with mean 0 and standard deviation 1.What is P(z < -2.1)?

The area to the left of the mean in any normal distribution is equal to _______.

Since a normal distribution curve extends from minus infinity to plus infinity, the area under the curve is infinity.

Participants in a 2 day biking event, cross the finish line at a rate of 10 bike riders per fifteen minute interval.The probability that less than 10 minutes will elapse between car arrivals is _____________.

For the normal approximation to be a good approximation for binomial distribution, n*p must be greater than ___________.

The height of the rectangle depicting a uniform distribution is the probability of each outcome and it is the same for all of the possible outcomes

If x is uniformly distributed over the interval 8 to 12, inclusively (8 $\le$ x $\le$ 12), then the probability, P(13 $\le$ x $\le$ 15), is __________________.

The probability that someone will prefer Coke over Pepsi is 0.56.A researcher asked 90 people which soda pop they preferred, and used the normal approximation to the binomial with a correction for continuity, what would be the probability at least 50 preferring Coke?

Within a range of z scores from -1 to +1, you can expect to find _______ per cent of the values in a normal distribution.

Suppose you are working with a data set that is normally distributed with a mean of 400 and a standard deviation of 20.Determine the most likely value of x such that 60% of the values are greater than x.

Binomial distributions in which the sample sizes are large may be approximated by a Poisson distribution.

The expected (mean)life of a particular type of light bulb is 1,000 hours with a standard deviation of 50 hours.The life of this bulb is normally distributed.Which most closely reflects the probability that a randomly selected bulb would last fewer than 940 hours?

The standard normal distribution is also called a finite distribution because its mean is zero and standard deviation one, always.

Suppose the total time to fill a routine prescription at a local pharmacy averages 35 minutes starting from the time the physician places the order to the time it is dispensed.Assume the standard deviation is 11 minutes.The z-score for x = 46 is ________.

Let z be a normal random variable with mean 0 and standard deviation 1.Which of these most closely reflects P(-2.25 < z < -1.1)?

Let z be a normal random variable with mean 0 and standard deviation 1.The 50^th percentile of z is most closely reflected by ____________.

In a busy gas station, an average of 2.4 cars arrive every minute.What is the average time between arrivals?

The net profit from a certain investment is normally distributed with a mean of $2,500 and a standard deviation of $1,000.The probability that the investor will not have a net loss is _____________.

Introduction to Statistics and Business Analytics

Visualizing Data With Charts and Graphs

Descriptive Statistics

Probability

Discrete Distributions

Sampling and Sampling Distributions

Statistical Inference: Estimation for Single Populations

Statistical Inference: Hypothesis Testing for Single Populations

Statistical Inferences About Two Populations

Analysis of Variance and Design of Experiments

Simple Regression Analysis and Correlation

Multiple Regression Analysis

Building Multiple Regression Models

Time-Series Forecasting and Index Numbers

Analysis of Categorical Data

Nonparametric Statistics

Statistical Quality Control

Decision Analysis

Filters

Exam 6: Continuous Distributions

Let z be a normal random variable with mean 0 and standard deviation 1.What is P(z < -2.1)?

The area to the left of the mean in any normal distribution is equal to _______.

Since a normal distribution curve extends from minus infinity to plus infinity, the area under the curve is infinity.

Participants in a 2 day biking event, cross the finish line at a rate of 10 bike riders per fifteen minute interval.The probability that less than 10 minutes will elapse between car arrivals is _____________.

For the normal approximation to be a good approximation for binomial distribution, n*p must be greater than ___________.

The height of the rectangle depicting a uniform distribution is the probability of each outcome and it is the same for all of the possible outcomes

If x is uniformly distributed over the interval 8 to 12, inclusively (8 ≤\le≤ x ≤\le≤ 12), then the probability, P(13 ≤\le≤ x ≤\le≤ 15), is __________________.

The probability that someone will prefer Coke over Pepsi is 0.56.A researcher asked 90 people which soda pop they preferred, and used the normal approximation to the binomial with a correction for continuity, what would be the probability at least 50 preferring Coke?

Within a range of z scores from -1 to +1, you can expect to find _______ per cent of the values in a normal distribution.

Suppose you are working with a data set that is normally distributed with a mean of 400 and a standard deviation of 20.Determine the most likely value of x such that 60% of the values are greater than x.

Binomial distributions in which the sample sizes are large may be approximated by a Poisson distribution.

The expected (mean)life of a particular type of light bulb is 1,000 hours with a standard deviation of 50 hours.The life of this bulb is normally distributed.Which most closely reflects the probability that a randomly selected bulb would last fewer than 940 hours?

The standard normal distribution is also called a finite distribution because its mean is zero and standard deviation one, always.

Suppose the total time to fill a routine prescription at a local pharmacy averages 35 minutes starting from the time the physician places the order to the time it is dispensed.Assume the standard deviation is 11 minutes.The z-score for x = 46 is ________.

Let z be a normal random variable with mean 0 and standard deviation 1.Which of these most closely reflects P(-2.25 < z < -1.1)?

Let z be a normal random variable with mean 0 and standard deviation 1.The 50th percentile of z is most closely reflected by ____________.

In a busy gas station, an average of 2.4 cars arrive every minute.What is the average time between arrivals?

The net profit from a certain investment is normally distributed with a mean of $2,500 and a standard deviation of $1,000.The probability that the investor will not have a net loss is _____________.

Introduction to Statistics and Business Analytics

Visualizing Data With Charts and Graphs

Descriptive Statistics

Probability

Discrete Distributions

Sampling and Sampling Distributions

Statistical Inference: Estimation for Single Populations

Statistical Inference: Hypothesis Testing for Single Populations

Statistical Inferences About Two Populations

Analysis of Variance and Design of Experiments

Simple Regression Analysis and Correlation

Multiple Regression Analysis

Building Multiple Regression Models

Time-Series Forecasting and Index Numbers

Analysis of Categorical Data

Nonparametric Statistics

Statistical Quality Control

Decision Analysis

Filters

If x is uniformly distributed over the interval 8 to 12, inclusively (8 $\le$ x $\le$ 12), then the probability, P(13 $\le$ x $\le$ 15), is __________________.

Let z be a normal random variable with mean 0 and standard deviation 1.The 50^th percentile of z is most closely reflected by ____________.