Question 1

If a particular normal distribution has a mean of 150 and a standard deviation of 5, the value 160 is _____ standard deviations away from the mean?

a

-1

b

+1

c

-2

d

+2

Question 2

The Standard Normal Distribution has a mean and standard deviation of...

a

(1, 1)

b

(0, 0)

c

(0, 1)

d

(1, 0)

Question 3

If we know that the length of time it takes a college student to find a parking spot in the library parking lot follows a normal distribution with a mean of 3.5 minutes and a standard deviation of 1 minute, find the point in the distribution in which 75.8% of the college students exceed when trying to find a parking spot in the library parking lot.

a

2.8 minutes

b

4.2 minutes

c

3.2 minutes

d

3.4 minutes

Question 4

The heights of all women between the ages of 25 and 30 is normally distributed with a mean of 61.6 inches and a standard deviation of 3.9 inches. What percentage of women are shorter than 61.6 inches?

a

50%

b

25%

c

75%

d

65%

Question 5

If we know that the length of time it takes a college student to find a parking spot in the library parking lot follows a normal distribution with a mean of 3.5 minutes and a standard deviation of 1 minute, find the probability that a randomly selected student will take between 2 and 4.5 minutes to find a parking spot in the library parking lot.

a

0.2255

b

0.7745

c

0.4938

d

0.0919

Question 6

Given below is the frequency distribution of the number of defective tomatoes in several different shipments.

Defective Items

Frequency

0 but less than 5

35

5 but less than 10

7

10 but less than 15

5

15 but less than 20

2

20 but less than 25

1

25 but less than 30

0

What is the approximate mean number of defective tomatoes?

a

10

b

8.3

c

4.3

d

5.2

Question 7

The Minister of Parliament for the area wanted to investigate the performance of businesses in Curepe. The table below provides data on the annual income of all firms in the Curepe region.

Class ($Millions)

Frequency

1 - 2

8

2.1 - 3

12

3.1 - 4

9

4.1 - 5

5

5.1 - 6

3

Total

37

What is the standard deviation of the distribution?

a

$2.1 Million

b

$1.21 Million

c

$3 Million

d

$1.9 Million

Question 8

Which measure of central tendency can be used for both numerical and categorical variables?

a

Median

b

Geometric mean

c

Mode

d

Arithmetic mean

Question 9

A researcher sampled 500 employees of a large firm to find out how many times they missed work in the last 3 months. The researcher derived a distribution with a mean and standard deviation of 7 and 5 respectively. Using Chebyshev's theorem, state the interval that captures the number of times 90% of the sampled employees missed work in the last 3 months.

a

7 (1 5)

b

7 (4 5)

c

7 (3.16 5)

d

7 (2.75 5)

Question 10

Which of the following statistics is not a measure of central tendency?

a

Median

b

Arithmetic mean

c

Q3

d

Mode

Question 11

A campus program evenly enrols thousands of undergraduate and graduate students. If a random sample of 4 students is selected from the program to be interviewed about the introduction of a new fast food outlet on the ground floor of the campus building, what is the probability that at least 2 of the students selected are undergraduate students?

a

0.25

b

0.3125

c

0.375

d

0.6875

Question 12

A packaging company has an old machine which improperly packages 30% of all its goods. The company has a special order to package 20 products for a client. How many products can we reasonably expect to be improperly packaged?

a

15

b

6

c

3

d

10

Question 13

Suppose the School of Business at USC enrols 4 times as many undergraduate students as graduate students (assume that total enrolment is in the thousands). If a random sample of 10 students is selected from the school to be interviewed about their level of satisfaction with the quality of the school's programs, what is the probability that all 10 students selected are undergraduate students?

a

0.107

b

0.03

c

0.5

d

0.33

Question 14

Suppose that 75% of the students enrolled in programs at the School of Business at USC enrols are undergraduate students and the rest are graduate students (assume that total enrolment is in the thousands). If a random sample of 10 students is selected from the school to be interviewed about their level of satisfaction with the quality of the school's programs, what is the probability that at least 8 of the students selected are graduate students?

a

0.146

b

0.244

c

0

d

0.031

Question 15

The economics department of a Caribbean university evenly enrols thousands of undergraduate and graduate students. If a random sample of 4 students is selected from the department to be interviewed about the introduction of a new fast food outlet, what is the probability that all 4 students selected are undergraduate students?

a

0.16

b

1

c

0.0625

d

0.0256