QSMT 3303 Quiz Ch 1-4

Which of the following is not a characteristic of an experiment where the binomial probability distribution is applicable?

the trails are dependent

The maximum yearly GDP growth rate for Asian countries for the period 2000-2004 is:

9.4

Being employed or unemployed is measured on which scale?

Nominal

Shirt sizes: XS, S, M, L, XL is measured on which scale:

Ordinal

Which of the following are qualitative scales of measurement? (multiple options may apply)

Ordinal and Nominal

The "random walk" theory of securities prices holds that price movements in disjoint time periods are independent of each other. Suppose that we record only whether the price is up or down each year, and that the probability that our portfolio rises in price in any one year is 0.65. (This probability is approximately correct for a portfolio containing equal dollar amounts of all common stocks listed on the New York Stock Exchange.) If you know that the portfolio has risen in price 2 years in a row, what probability do you assign to the event that it will go down next year?

P ( our portfolio goes down at the third year )= 0.35

A string of holiday lights contains 5 lights. The lights are wired in series, so that if any light fails the whole string will go dark. Each light has probability 0.02 of failing during a 3-year period. The lights fail independently of each other. What is the probability that the string of lights will remain bright for 3 years?

P(all 5 lights work for 3 years ) = 0.9039

The expected value of a random variable is the

none of the answers is correct

The second quartile of the distribution of yearly GDP growth rate for Asian countries for the period 2000-2004 is:

4.65

A sample was taken of the salaries of 20 employees of a large company. The following are the salaries (in thousands of dollars) for this year. For convenience, the data are ordered. 28 31 34 35 37 41 42 42 42 47 49 51 52 52 60 61 67 72 75 77 The median salary of the 20 employees is:

48,000

Instead of producing customized printers, suppose that HP decides to produce generic printers (without the specific power supply) and installs the power supplies for each destination country after observing the actual demand. (This strategy is often referred to as postponement in supply chain management, or delayed differentiation). Note that the decision on how much generic printers to produce depends on the total demand and needs to be taken before observing the total demand D = D1 + D2. Keeping this in mind, the standard deviation of the total demand D is:

5

The third quartile of the distribution of yearly GDP growth rate for Asian countries for the period 2000-2004 is:

5.8

Assume that the random variable X follows a binomial B(100, 0.5). The expected value of this distribution is

50

Instead of producing customized printers, suppose that HP decides to produce generic printers (without the specific power supply) and installs the power supplies for each destination country after observing the actual demand. (This strategy is often referred to as postponement in supply chain management, or delayed differentiation). Note that the decision on how much generic printers to produce depends on the total demand and needs to be taken before observing the total demand D = D1 + D2. Keeping this in mind, the expected value of the total demand D is:

50

In a binomial experiment consisting of five trials, the number of different values that x (the number of successes) can assume is

6

Instead of producing customized printers, suppose that HP decides to produce generic printers (without the specific power supply) and installs the power supplies for each destination country after observing the actual demand. (This strategy is often referred to as postponement in supply chain management, or delayed differentiation). Note that the decision on how much generic printers to produce depends on the total demand and needs to be taken before observing the total demand D = D1 + D2. Keeping this in mind, the total generic printers produced (according to the rule of thumb) is:

65

Hewlett Packard (HP) sells printers with different voltage and plug requirements in France and USA. The voltage requirement for France is 230V and for USA is 120V. The demand for printers in France, D1 is a random variable with mean 30 units and a standard deviation of 3 units. The demand for printers in USA, D2 is a random variable with mean 20 units and a standard deviation of 4 units. Assume that D1 and D2 are independent. Printers are manufactured in advance (before observing actual demand) using the following rule of thumb: Amount of printers produced = Mean Demand + 3*(Standard deviation of Demand) \ Suppose that HP produces an X1 number of printers (with voltage = 230V) for France and X2 number of printers (with voltage = 120V) for USA. What is the total number of printers HP produced (X1 + X2):

71

Last year a small accounting firm paid each of its five clerks $30,000, two junior accountants $65,000 each, and the firm's owner $355,000. What is the mean salary paid at the firm: (Hint: You need to use the Weighted Mean formula.)

78,375

A sample of the percentage increase in five growth funds over a one-year period: 8.9% 12.2% 13.7% 14.4% 9.8% The median percentage increase in this sample is:

12.2 %

The "random walk" theory of securities prices holds that price movements in disjoint time periods are independent of each other. Suppose that we record only whether the price is up or down each year, and that the probability that our portfolio rises in price in any one year is 0.65. (This probability is approximately correct for a portfolio containing equal dollar amounts of all common stocks listed on the New York Stock Exchange.) What is the probability that the portfolio's value moves in the same direction in both of the next 2 years? Round your answer to 3 decimal places.

0.545

Let A through F represent the following occupations in order: A - Managerial; B - Technical, sales, administrative support; C - Service Occupations; D - Precision production, craft and repair; E - Operators, fabricators, and laborers; F - Farming, forestry and fishing. Class A B C D E F Male 0.14 0.11 0.06 0.11 0.12 0.03 Female 0.09 0.20 0.08 0.01 0.04 0.01 The table above gives the probability distribution of the gender and occupation of a randomly chosen American worker. Using this information, what is the probability that a female worker works in a job that belongs to either Category D or Category E? (Round your answer to 4 decimal places).

0.05

A factory employs several thousand workers, of whom 30% are Hispanic. Out of 15 randomly chosen workers, what is the probability that exactly 3 of them are Hispanic? Give your answer to 4 decimal places.

0.1700

Let A through F represent the following occupations in order: A - Managerial; B - Technical, sales, administrative support; C - Service Occupations; D - Precision production, craft and repair; E - Operators, fabricators, and laborers; F - Farming, forestry and fishing. The table below gives the probability distribution of the gender and occupation of a randomly chosen American worker. Class A B C D E F Male 0.14 0.11 0.06 0.11 0.12 0.03 Female 0.09 0.20 0.08 0.01 0.04 0.01 What is the conditional probability that a worker is female, given that a worker holds a job in either Category D or Category E? (Please round your answer to 4 decimal places).

0.1786

A factory employs several thousand workers, of whom 30% are Hispanic. Out of 15 randomly chosen workers, what is the probability that 3 or fewer of them are Hispanic? Give your answer to 3 decimal places.

0.297

Let A through F represent the following occupations in order: A - Managerial; B - Technical, sales, administrative support; C - Service Occupations; D - Precision production, craft and repair; E - Operators, fabricators, and laborers; F - Farming, forestry and fishing. Class A B C D E F Male 0.14 0.11 0.06 0.11 0.12 0.03 Female 0.09 0.20 0.08 0.01 0.04 0.01 The table above gives the probability distribution of the gender and occupation of a randomly chosen American worker. Find the conditional probability that the worker is female, given that the worker chosen holds a managerial (Category A) job (round your answer to 4 decimal places).

0.3913

A factory employs several thousand workers, of whom 30% are Hispanic. Out of 15 randomly chosen workers, what is the probability that there are 3 to 5 Hispanic among them? Give your answer to 3 decimal places.

0.595

Consolidated Builders has submitted bid for two large construction projects. The company president believes that the probability of winning the first contract (event A) is 0.6, that the probability of winning the second (event B) is 0.5, and that the probability of winning both jobs is 0.3. What is the probability that the Consolidated Builders will win at least one of these two jobs?

0.80

The Standard deviation is

1.43

The Variance is

2.05

The following table contains the growth of gross domestic product (percent per year) for the period 2000 to 2004 in countries in Asia (not including Japan): Country Growth Bangladesh 5.2 China 9.4 Hong Kong 3.2 India 6.2 Indonesia 4.6 Korea (South) 4.7 Malaysia 4.4 Pakistan 4.1 Philippines 3.9 Singapore 2.9 Thailand 5.4 Vietnam 7.2 Use this information to answer the questions in this Part 3. Question 8 of 19 1.0 Points The minimum yearly GDP growth rate for Asian countries for the period 2000-2004 is:

2.9

AMR is a computer-consulting firm. The number of new clients that they have obtained each month has ranged from 0 to 6. The number of new clients has the probability distribution that is shown below. # of New Clients Probability 0 0.05 1 0.10 2 0.15 3 0.35 4 0.20 5 0.10 6 0.05 The expected number of new clients per month is

3.05

Twenty percent of students in a class are planning to go to graduate school. Suppose that a random sample of 100 students is selected from this class. Let X be the number of students who are planning to go to graduate school out of these 100 students. The standard deviation of X is

4

The first quartile of the distribution of yearly GDP growth rate for Asian countries for the period 2000-2004 is:

4.0

Which of the following are quantitative scales of measurement? (multiple options may apply)

Ratio and Interval

Compare the total printers produced with and without the postponement strategy. Based on these two values, what do you conclude:

With the help of postponement, HP is able to pool demand across France and USA, which reduces variability and the total number of printers produced.

Consider the following experiment: A company uses a computer-based system to teach clerical employees new office software. After a lesson, the computer presents 10 exercises. The student solves each exercise and enters the answer. The computer gives additional instruction between exercises if the answer is wrong. Let X be the number of exercises that the student gets right. Does X have a binomial distribution? Give your reasons.

X does not have a Binomial distribution since the probability for a right answer is not the same in all trials.

The weight of an object, measured in grams, is an example of

a continuous random variable

When using Excel's BINOM.DIST function, one should choose TRUE for the fourth input if

a cumulative probability is desired

The number of customers that enter a store during one day is an example of

a discrete random variable

The weight of an object, measured (or rounded) to the nearest gram, is an example of

a discrete random variable

Variance is

a measure of the dispersion of a random variable

Excel's BINOM.DIST function can be used to compute

both binomial probabilities and cumulative binomial probabilities

An experiment consists of measuring the speed of automobiles on a highway by the use of radar equipment. The random variable in this experiment is speed, measured in miles per hour. This random variable is a

continuous random variable