Question 1

Use the standard normal distribution to find $$P ( 0 < z < 2.25 )$$

Accepted Answer

A) .5122 
B) .7888 
C) .8817 
D) .4878 
A) .5122 
B) .7888 
C) .8817 
D) .4878

Question 2

The volume of soda a dispensing machine pours into a 12-ounce can of soda follows a normal distribution with a mean of 12.45 ounces and a standard deviation of 0.30 ounce. The company
Receives complaints from consumers who actually measure the amount of soda in the cans and
Claim that the volume is less than the advertised 12 ounces. What proportion of the soda cans
Contain less than the advertised 12 ounces of soda?

Accepted Answer

A) .9332 
B) .5668 
C) .4332 
D) .0668 
A) .9332 
B) .5668 
C) .4332 
D) .0668

Question 3

Nearly 100% of the observed occurrences of a random variable x that is normally distributed will
fall within three standard deviations of the mean of the distribution of x.

Accepted Answer

A) True 
 B)False

Question 4

A paint machine dispenses dye into paint cans to create different shades of paint. The amount of dye dispensed into a can is known to have a normal distribution with a mean of 5 milliliters (ml)
And a standard deviation of 0.4 ml. Answer the following questions based on this information.
What proportion of the paint cans contain less than 5.54 ml of the dye?

Accepted Answer

A) 0.9115 
B) 0.5885 
C) 0.9885 
D) 0.0885 
A) 0.9115 
B) 0.5885 
C) 0.9885 
D) 0.0885

Question 5

The weight of corn chips dispensed into a 12-ounce bag by the dispensing machine has been identified as possessing a normal distribution with a mean of 12.5 ounces and a standard deviation
Of 0.2 ounce. What proportion of the 12-ounce bags contain more than the advertised 12 ounces of
Chips?

Accepted Answer

A) .0062 
B) .5062 
C) .4938 
D) .9938 
A) .0062 
B) .5062 
C) .4938 
D) .9938

Question 6

IQ test scores are normally distributed with a mean of 103 and a standard deviation of 12 . An individual's IQ score is found to be 113 . Find the $z$-score corresponding to this value.

Accepted Answer

A)  $1.20$ 
B)  $- 1.20$ 
C)  $0.83$ 
D)  $- 0.83$ 
A)  $1.20$ 
B)  $- 1.20$ 
C)  $0.83$ 
D)  $- 0.83$

Question 7

Suppose x is a random variable best described by a uniform probability distribution with c = 3 and d = 7. Find the value of a that makes the following probability statement true: $\mathrm { P } ( \mathrm { x } \leq \mathrm { a } ) = 0.75$

Accepted Answer

A) 4 
B) 5.8 
C) 3 
D) 6 
A) 4 
B) 5.8 
C) 3 
D) 6

Question 8

Use the standard normal distribution to find $$P ( - 2.25 < z < 0 )$$

Accepted Answer

A) .0122 
B) .5122 
C) .6831 
D) .4878 
A) .0122 
B) .5122 
C) .6831 
D) .4878

Question 9

Which one of the following suggests that the data set is not approximately normal?

Accepted Answer

A)  A data set with $68 \%$ of the measurements within $\bar { x } \pm 2 \mathrm {~s}$. 
B)  A data set with IQR $= 752$ and $s = 574$. 
C) 
  
D) 
  
A)  A data set with $68 \%$ of the measurements within $\bar { x } \pm 2 \mathrm {~s}$. 
B)  A data set with IQR $= 752$ and $s = 574$. 
C) 
  
D)

Question 10

The time between arrivals at an ATM machine follows an exponential distribution with θ = 10 minutes. Find the mean and standard deviation of this distribution.

Accepted Answer

A) Mean = 10, Standard Deviation = 100 
B) Mean = 10, Standard Deviation = 3.16 
C) Mean = 10, Standard Deviation = 10 
D) Mean = 3.16, Standard Deviation = 3.16 
A) Mean = 10, Standard Deviation = 100 
B) Mean = 10, Standard Deviation = 3.16 
C) Mean = 10, Standard Deviation = 10 
D) Mean = 3.16, Standard Deviation = 3.16

Question 11

For a continuous probability distribution, the probability that x is between a and b is the same
regardless of whether or not you include the endpoints, a and b, of the interval.

Accepted Answer

A) True 
 B)False

Question 12

Farmers often sell fruits and vegetables at roadside stands during the summer. One such
roadside stand has a daily demand for tomatoes that is approximately normally
distributed with a mean of 128 tomatoes and a standard deviation of 30 tomatoes. How
many tomatoes must be available on any given day so that there is only a 1.5% chance that
all tomatoes will be sold?

Accepted Answer

Let @#LAT-DLM& be the number of tomatoes

Question 13

High temperatures in a certain city for the month of August follow a uniform distribution over the interval 60°F to 92°F. What is the probability that the high temperature on a day in August exceeds
65°F?

Accepted Answer

A) 0.4276 
B) 0.0313 
C) 0.8438 
D) 0.1562 
A) 0.4276 
B) 0.0313 
C) 0.8438 
D) 0.1562

Question 14

Suppose $x$ is a random variable best described by a uniform probability distribution with $c = 3$ and $d = 9$. Find the value of a that makes the following probability statement true: $\mathrm { P } ( \mathrm { x } \leq \mathrm { a } ) = 1$.

Accepted Answer

A)  $a \leq 3$ 
B)  $a \geq 3$ 
C)  $a \leq 9$ 
D)  $a \geq 9$ 
A)  $a \leq 3$ 
B)  $a \geq 3$ 
C)  $a \leq 9$ 
D)  $a \geq 9$

Question 15

The probability density function for an exponential random variable x has a graph called a bell
curve.

Accepted Answer

A) True 
 B)False

Question 16

Determine if it is appropriate to use the normal distribution to approximate a binomial
distribution when n = 11 and p = 0.3.

Accepted Answer

cannot use

Question 17

Suppose x is a uniform random variable with $c = 10 \text { and } d = 50 \text {. Find } P ( 13 < x < 45 )$ Round to the nearest hundredth when necessary.

Accepted Answer

A) 0.5 
B) 0.8 
C) 1 
D) 0.2 
A) 0.5 
B) 0.8 
C) 1 
D) 0.2

Question 18

The continuity correction factor is the name given to the .5 adjustment necessary when estimating
the binomial with the normal distribution.

Accepted Answer

A) True 
 B)False

Question 19

The printout below contains summary statistics of the heights of a sample of 200 adult
men in the United States.
Descriptive Statistics: HT $$\begin{array} { | l | l | l | l | l | l | l | l | l } 
\hline \text { Variable } & \mathrm { N } & \text { Mean } & \text { StDev } & \text { Minimum } & \text { Q1 } & \text { Median } & \text { Q2 } & \text { Mi } \
\hline \text { HT } & 200 & 70.187 & 2.716 & 62.375 & 67.875 & 69.625 & 71.500 & 91 \
\hline
\end{array}$$ Use the information in the printout to determine whether the distribution of heights is
approximately normal. Explain your reasoning.

Accepted Answer

@#LAT-DLM&; Since this number

Question 20

Which geometric shape is used to represent areas for a uniform distribution?

Accepted Answer

A) Triangle 
B) Bell curve 
C) Circle 
D) Rectangle 
A) Triangle 
B) Bell curve 
C) Circle 
D) Rectangle

Use the standard normal distribution to find $P ( 0 < z < 2.25 )$

Nearly 100% of the observed occurrences of a random variable x that is normally distributed will fall within three standard deviations of the mean of the distribution of x.

The weight of corn chips dispensed into a 12-ounce bag by the dispensing machine has been identified as possessing a normal distribution with a mean of 12.5 ounces and a standard deviation Of 0.2 ounce. What proportion of the 12-ounce bags contain more than the advertised 12 ounces of Chips?

IQ test scores are normally distributed with a mean of 103 and a standard deviation of 12 . An individual's IQ score is found to be 113 . Find the $z$ -score corresponding to this value.

Suppose x is a random variable best described by a uniform probability distribution with c = 3 and d = 7. Find the value of a that makes the following probability statement true: $\mathrm { P } ( \mathrm { x } \leq \mathrm { a } ) = 0.75$

Use the standard normal distribution to find $P ( - 2.25 < z < 0 )$

Which one of the following suggests that the data set is not approximately normal?

The time between arrivals at an ATM machine follows an exponential distribution with θ = 10 minutes. Find the mean and standard deviation of this distribution.

For a continuous probability distribution, the probability that x is between a and b is the same regardless of whether or not you include the endpoints, a and b, of the interval.

High temperatures in a certain city for the month of August follow a uniform distribution over the interval 60°F to 92°F. What is the probability that the high temperature on a day in August exceeds 65°F?

Suppose $x$ is a random variable best described by a uniform probability distribution with $c = 3$ and $d = 9$ . Find the value of a that makes the following probability statement true: $\mathrm { P } ( \mathrm { x } \leq \mathrm { a } ) = 1$ .

The probability density function for an exponential random variable x has a graph called a bell curve.

Determine if it is appropriate to use the normal distribution to approximate a binomial distribution when n = 11 and p = 0.3.

Suppose x is a uniform random variable with $c = 10 \text { and } d = 50 \text {. Find } P ( 13 < x < 45 )$ Round to the nearest hundredth when necessary.

The continuity correction factor is the name given to the .5 adjustment necessary when estimating the binomial with the normal distribution.

Which geometric shape is used to represent areas for a uniform distribution?

Statistics, Data, and Statistical Thinking

Methods for Describing Sets of Data

Probability

Discrete Random Variables

Sampling Distributions

Inferences Based on a Single Sample: Estimation With Confidence Intervals

Inferences Based on a Single

Inferences Based on Two Samples: Confidence Intervals and Tests of Hypotheses

Analysis of Variance: Comparing More Than Two Means

Simple Linear Regression

Multiple Regression and Model Building

Categorical Data Analysis

Nonparametric Statistics Available Online

Filters

Exam 5: Continuous Random Variables

Use the standard normal distribution to find P(0<z<2.25)P ( 0 < z < 2.25 )P(0<z<2.25)

Nearly 100% of the observed occurrences of a random variable x that is normally distributed will fall within three standard deviations of the mean of the distribution of x.

The weight of corn chips dispensed into a 12-ounce bag by the dispensing machine has been identified as possessing a normal distribution with a mean of 12.5 ounces and a standard deviation Of 0.2 ounce. What proportion of the 12-ounce bags contain more than the advertised 12 ounces of Chips?

IQ test scores are normally distributed with a mean of 103 and a standard deviation of 12 . An individual's IQ score is found to be 113 . Find the zzz -score corresponding to this value.

Suppose x is a random variable best described by a uniform probability distribution with c = 3 and d = 7. Find the value of a that makes the following probability statement true: P(x≤a)=0.75\mathrm { P } ( \mathrm { x } \leq \mathrm { a } ) = 0.75P(x≤a)=0.75

Use the standard normal distribution to find P(−2.25<z<0)P ( - 2.25 < z < 0 )P(−2.25<z<0)

Which one of the following suggests that the data set is not approximately normal?

The time between arrivals at an ATM machine follows an exponential distribution with θ = 10 minutes. Find the mean and standard deviation of this distribution.

For a continuous probability distribution, the probability that x is between a and b is the same regardless of whether or not you include the endpoints, a and b, of the interval.

High temperatures in a certain city for the month of August follow a uniform distribution over the interval 60°F to 92°F. What is the probability that the high temperature on a day in August exceeds 65°F?

Suppose xxx is a random variable best described by a uniform probability distribution with c=3c = 3c=3 and d=9d = 9d=9 . Find the value of a that makes the following probability statement true: P(x≤a)=1\mathrm { P } ( \mathrm { x } \leq \mathrm { a } ) = 1P(x≤a)=1 .

The probability density function for an exponential random variable x has a graph called a bell curve.

Determine if it is appropriate to use the normal distribution to approximate a binomial distribution when n = 11 and p = 0.3.

Suppose x is a uniform random variable with c=10 and d=50. Find P(13<x<45)c = 10 \text { and } d = 50 \text {. Find } P ( 13 < x < 45 )c=10 and d=50. Find P(13<x<45) Round to the nearest hundredth when necessary.

The continuity correction factor is the name given to the .5 adjustment necessary when estimating the binomial with the normal distribution.

Which geometric shape is used to represent areas for a uniform distribution?

Statistics, Data, and Statistical Thinking

Methods for Describing Sets of Data

Probability

Discrete Random Variables

Sampling Distributions

Inferences Based on a Single Sample: Estimation With Confidence Intervals

Inferences Based on a Single

Inferences Based on Two Samples: Confidence Intervals and Tests of Hypotheses

Analysis of Variance: Comparing More Than Two Means

Simple Linear Regression

Multiple Regression and Model Building

Categorical Data Analysis

Nonparametric Statistics Available Online

Filters

Use the standard normal distribution to find $P ( 0 < z < 2.25 )$

IQ test scores are normally distributed with a mean of 103 and a standard deviation of 12 . An individual's IQ score is found to be 113 . Find the $z$ -score corresponding to this value.

Suppose x is a random variable best described by a uniform probability distribution with c = 3 and d = 7. Find the value of a that makes the following probability statement true: $\mathrm { P } ( \mathrm { x } \leq \mathrm { a } ) = 0.75$

Use the standard normal distribution to find $P ( - 2.25 < z < 0 )$

Suppose $x$ is a random variable best described by a uniform probability distribution with $c = 3$ and $d = 9$ . Find the value of a that makes the following probability statement true: $\mathrm { P } ( \mathrm { x } \leq \mathrm { a } ) = 1$ .

Suppose x is a uniform random variable with $c = 10 \text { and } d = 50 \text {. Find } P ( 13 < x < 45 )$ Round to the nearest hundredth when necessary.