Topics 5-6 Business Statistics FCs
(straighterline) – Questions with Solved
Solutions
A company is studying the number of monthly absences among its 125 employees. The
following probability distribution shows the likelihood that people were absent 0, 1, 2, 3,
4, or 5 days last month.
Number of Days Absent/Probability
0 0.60
1 0.20
2 0.12
3 0.04
4 0.04
5 0.00
What is the variance of the number of days absent? - -ANSWER--1.1616
Mean = (0x0.60)+(1x0.20)+(2x0.12)+(3x0.04)+(4x0.04) = 0.72
Variance = (0-0.72)^2 x 0.60 + (1-0.72)^2 × 0.20 + (2-0.72)^2 × 0.12 + (3-0.72)^2 × 0.04
+ (4-0.72)^2 × 0.04
The following is a binomial probability distribution with n = 3 and π = 0.20.
X/P(x)
0 0.027
1 0.189
2 0.441
3 0.343
The mean of the distribution is _______. - -ANSWER--0.60
For the following distribution:
X/P(x)
0 0.027
, 1 0.189
2 0.441
3 0.343
What is the mean of the distribution? - -ANSWER--2.1
A statistics professor receives an average of five e-mail messages per day from
students. Assume the number of messages approximates a Poisson distribution. What
is the probability that on a randomly selected day she will have two messages? - -
ANSWER--0.0842
A company is studying the number of monthly absences among its 125 employees. The
following probability distribution shows the likelihood that people were absent 0, 1, 2, 3,
4, or 5 days last month.
Number of Days Absent/Probability
0 0.60
1 0.20
2 0.12
3 0.04
4 0.04
5 0.00
What is the standard deviation of the number of days absent? - -ANSWER--1.0778
A company is studying the number of monthly absences among its 125 employees. The
following probability distribution shows the likelihood that people were absent 0, 1, 2, 3,
4, or 5 days last month.
Number of Days Absent/Probability
0 0.60
1 0.20
2 0.12
3 0.04
4 0.04
5 0.00
Given the probability distribution, which of the following predictions is correct? - -
ANSWER--There is a 0.12 probability that an employee will be absent two days per
month.
Which shape describes a Poisson distribution? - -ANSWER--Positively skewed
The following is a binomial probability distribution with n = 3 and π = 0.20.
X/P(x)
(straighterline) – Questions with Solved
Solutions
A company is studying the number of monthly absences among its 125 employees. The
following probability distribution shows the likelihood that people were absent 0, 1, 2, 3,
4, or 5 days last month.
Number of Days Absent/Probability
0 0.60
1 0.20
2 0.12
3 0.04
4 0.04
5 0.00
What is the variance of the number of days absent? - -ANSWER--1.1616
Mean = (0x0.60)+(1x0.20)+(2x0.12)+(3x0.04)+(4x0.04) = 0.72
Variance = (0-0.72)^2 x 0.60 + (1-0.72)^2 × 0.20 + (2-0.72)^2 × 0.12 + (3-0.72)^2 × 0.04
+ (4-0.72)^2 × 0.04
The following is a binomial probability distribution with n = 3 and π = 0.20.
X/P(x)
0 0.027
1 0.189
2 0.441
3 0.343
The mean of the distribution is _______. - -ANSWER--0.60
For the following distribution:
X/P(x)
0 0.027
, 1 0.189
2 0.441
3 0.343
What is the mean of the distribution? - -ANSWER--2.1
A statistics professor receives an average of five e-mail messages per day from
students. Assume the number of messages approximates a Poisson distribution. What
is the probability that on a randomly selected day she will have two messages? - -
ANSWER--0.0842
A company is studying the number of monthly absences among its 125 employees. The
following probability distribution shows the likelihood that people were absent 0, 1, 2, 3,
4, or 5 days last month.
Number of Days Absent/Probability
0 0.60
1 0.20
2 0.12
3 0.04
4 0.04
5 0.00
What is the standard deviation of the number of days absent? - -ANSWER--1.0778
A company is studying the number of monthly absences among its 125 employees. The
following probability distribution shows the likelihood that people were absent 0, 1, 2, 3,
4, or 5 days last month.
Number of Days Absent/Probability
0 0.60
1 0.20
2 0.12
3 0.04
4 0.04
5 0.00
Given the probability distribution, which of the following predictions is correct? - -
ANSWER--There is a 0.12 probability that an employee will be absent two days per
month.
Which shape describes a Poisson distribution? - -ANSWER--Positively skewed
The following is a binomial probability distribution with n = 3 and π = 0.20.
X/P(x)
