Chapter 2 Probability Concepts and Applications

111) The number of cars passing through an intersection in the next five minutes can usually be described by the

A) normal distribution.

B) uniform distribution.

C) exponential distribution.

D) Poisson distribution.

E) None of the above

112) Arrivals at a fast-food restaurant follow a Poisson distribution with a mean arrival rate of 16 customers per hour. What is the probability that in the next hour there will be exactly 12 arrivals?

A) 0.0000

B) 0.0661

C) 0.7500

D) 0.1322

E) None of the above

113) Arrivals at a fast-food restaurant follow a Poisson distribution with a mean arrival rate of 16 customers per hour. What is the probability that in the next hour there will be exactly 8 arrivals?

A) 1.000

B) 0.200

C) 0.175

D) 0.825

E) None of the above

114) The number of calls received by call center follows a Poisson process with a rate of 1.5 per minute. What is the probability that a minute goes by without a call?

A) 0

B) 0.223

C) 0.500

D) 0.558

E) 1

115) Which of the following statements concerning the F distribution is true?

A) The F distribution is discrete.

B) The F distribution is symmetrical.

C) The F distribution is useful in modeling customer arrivals.

D) The F distribution is useful in testing hypotheses about variance.

E) The F distribution is interchangeable with the normal distribution for large sample sizes.

116) What is the F value associated with ? = 0.05, numerator degrees of freedom (df1) equal to 4, and denominator degrees of freedom (df2) equal to 9?

A) 3.63

B) 1.80

C) 6.0

D) 0.11

E) 0.18

117) Given a df1 = 3 and df2 = 6, what is the probability that F is greater than 4.3?

A) 0.0610

B) 0.1294

C) 0.05

D) 0.5

E) Not enough information provided

118) What is the probability that F is between 4 and 5, given a df1 = 4 and df2 = 6?

A) 0.0654

B) 0.0406

C) 0.0248

D) 0.05

E) Not enough information provided

119) Which of the following characteristics is not true for the exponential distribution?

A) It is discrete probability distribution.

B) It is also called the negative exponential distribution.

C) It is used in dealing with queuing problems.

D) It is used to describe the times between customer arrivals.

E) The variance is the square of the expected value.

120) The length of time that it takes the tollbooth attendant to service each driver can typically be described by the

A) normal distribution.

B) uniform distribution.

C) exponential distribution.

D) Poisson distribution.

E) None of the above

121) The Department of Motor Vehicles (DMV) can service customers at a rate of 20 per hour (or 1/3 per minute) when it comes to license renewals. The service time follows an exponential distribution. What is the probability that it will take less than 2 minutes for a particular customer to get a license renewal?

A) 1

B) 0.487

C) 0.513

D) 0

E) 0.1

122) The Department of Motor Vehicles (DMV) can service customers at a rate of 20 per hour (or 1/3 per minute) when it comes to license renewals. The service time follows an exponential distribution. What is the probability that it will take less than 3 minutes for a particular customer to get a license renewal?

A) 0.5

B) 0

C) 1

D) 0.368

E) 0.632

123) The Department of Motor Vehicles (DMV) can service customers at a rate of 20 per hour (or 1/3 per minute) when it comes to license renewals. The service time follows an exponential distribution. What is the probability that it will take between 2 and 3 minutes to be served?

A) 0.4831

B) 0

C) 1

D) 0.1419

E) 0.6284

124) Drivers arrive at a toll booth at a rate of 3 per minute during peak traffic periods. The time between consecutive driver arrivals follows an exponential distribution. What is the probability that it will take less than 1/2 of a minute between consecutive drivers?

A) 0.167

B) 0.223

C) 0.777

D) 0.5

E) 1

125) Drivers arrive at a toll booth at a rate of 3 per minute during peak traffic periods. The time between consecutive driver arrivals follows an exponential distribution. What is the probability that it will take more than 1/3 of a minute between consecutive drivers?

A) 0.632

B) 0.111

C) 0.368

D) 0.208

E) Not enough information given