Question 1

Instruction 6.4
The manager of a surveying company believes that the average number of phone surveys completed per hour by her employees has a normal distribution. She takes a sample of 15 days' output from her employees and determines the average number of surveys per hour on these days. The ordered array for this data is: 10.0, 10.1, 10.3, 10.5, 10.7, 11.2, 11.4, 11.5, 11.7, 11.8, 11.8, 12.0, 12.2, 12.2, 12.5.
-Referring to Instruction 6.4,the fourth standard normal quantile is_______

Accepted Answer

The answer of Instruction 6.4
The manager of a surveying company...

Question 2

Instruction 6.5
The city manager of a large city believes that the number of reported accidents on any weekend has a normal distribution. She takes a sample of nine weekends and determines the number of reported accidents during each. The ordered array for this data is: 15, 46, 53, 54, 55, 76, 82, 256, 407.
-Referring to Instruction 6.5,the sixth standard normal quantile is _______

Accepted Answer

The answer of Instruction 6.5
The city manager of a large...

Question 3

A catalogue company that receives the majority of its orders by telephone conducted a study to determine how long customers were willing to wait on hold before ordering a product.The length of time was found to be a random variable best approximated by an exponential distribution with a mean equal to 3 minutes.
-What proportion of customers having to hold more than 4.5 minutes will hang up before placing an order?
A) 0.51342
B) 0.48658
C) 0.22313
D) 0.77687

Accepted Answer

The answer of A catalogue company that receives the majority...

Question 4

Instruction 6.5
The city manager of a large city believes that the number of reported accidents on any weekend has a normal distribution. She takes a sample of nine weekends and determines the number of reported accidents during each. The ordered array for this data is: 15, 46, 53, 54, 55, 76, 82, 256, 407.
-Referring to Instruction 6.5,the data appear normal.

Accepted Answer

The data does not appear normal because it is heavily skewed to the right, with most values clustered at the lower end and a few very high values (256, 407) distorting the distribution.

Question 5

The true length of boards cut at a mill with a listed length of 3 metres is normally distributed with a mean of 303 cm and a standard deviation of 1 cm.What proportion of the boards will be between 301 and 304 cm?

Accepted Answer

The answer of The true length of boards cut at...

Question 6

Instruction 6.4
The manager of a surveying company believes that the average number of phone surveys completed per hour by her employees has a normal distribution. She takes a sample of 15 days' output from her employees and determines the average number of surveys per hour on these days. The ordered array for this data is: 10.0, 10.1, 10.3, 10.5, 10.7, 11.2, 11.4, 11.5, 11.7, 11.8, 11.8, 12.0, 12.2, 12.2, 12.5.
-Referring to Instruction 6.4,the first standard normal quantile is ________.

Accepted Answer

The answer of Instruction 6.4
The manager of a surveying company...

Question 7

Instruction 6.4
The manager of a surveying company believes that the average number of phone surveys completed per hour by her employees has a normal distribution. She takes a sample of 15 days' output from her employees and determines the average number of surveys per hour on these days. The ordered array for this data is: 10.0, 10.1, 10.3, 10.5, 10.7, 11.2, 11.4, 11.5, 11.7, 11.8, 11.8, 12.0, 12.2, 12.2, 12.5.
-Referring to Instruction 6.4,the data appear reasonably normal but not perfectly normal.

Accepted Answer

While the data may not be perfectly normal, the fact that the sample size is 15 and the data falls within a reasonable range (between 10 and 12.5) suggests that it is reasonably normal.

Question 8

When constructing a normal probability plot,the Z values are plotted on the vertical axis and the corresponding values of the variable are plotted on the horizontal axis.

Accepted Answer

In a normal probability plot, the Z values (standard scores) are plotted on the horizontal axis, and the corresponding values of the variable are plotted on the vertical axis.

Question 9

If a data batch is approximately normally distributed,its normal probability plot would be S-shaped.

Accepted Answer

If a data batch is approximately normally distributed, its normal probability plot would be a straight line, not S-shaped. An S-shaped normal probability plot would indicate that the data deviates from normality.

Question 10

Instruction 6.5
The city manager of a large city believes that the number of reported accidents on any weekend has a normal distribution. She takes a sample of nine weekends and determines the number of reported accidents during each. The ordered array for this data is: 15, 46, 53, 54, 55, 76, 82, 256, 407.
-Referring to Instruction 6.5,the fifth standard normal quantile is_______

Accepted Answer

The answer of Instruction 6.5
The city manager of a large...

Question 11

Instruction 6.5
The city manager of a large city believes that the number of reported accidents on any weekend has a normal distribution. She takes a sample of nine weekends and determines the number of reported accidents during each. The ordered array for this data is: 15, 46, 53, 54, 55, 76, 82, 256, 407.
-Referring to Instruction 6.5,construct a normal probability plot.

Accepted Answer

The answer of Instruction 6.5
The city manager of a large...

Question 12

A normal probability plot may be used to assess the assumption of normality for a particular batch of data.

Accepted Answer

A normal probability plot is a graphical tool used to check if a dataset follows a normal distribution. Therefore, it can be used to assess the assumption of normality for a particular batch of data.

Question 13

Instruction 6.4
The manager of a surveying company believes that the average number of phone surveys completed per hour by her employees has a normal distribution. She takes a sample of 15 days' output from her employees and determines the average number of surveys per hour on these days. The ordered array for this data is: 10.0, 10.1, 10.3, 10.5, 10.7, 11.2, 11.4, 11.5, 11.7, 11.8, 11.8, 12.0, 12.2, 12.2, 12.5.
-Referring to Instruction 6.4,construct a normal probability plot for the data.

Accepted Answer

The answer of Instruction 6.4
The manager of a surveying company...

Question 14

The amount of pyridoxine (in grams)in a multiple vitamin is normally distributed with μ = 110 grams and σ = 25 grams.Approximately 83% of the vitamins will have at least how many grams of pyridoxine?

Accepted Answer

The answer of The amount of pyridoxine (in grams)in a...

Question 15

Instruction 6.4
The manager of a surveying company believes that the average number of phone surveys completed per hour by her employees has a normal distribution. She takes a sample of 15 days' output from her employees and determines the average number of surveys per hour on these days. The ordered array for this data is: 10.0, 10.1, 10.3, 10.5, 10.7, 11.2, 11.4, 11.5, 11.7, 11.8, 11.8, 12.0, 12.2, 12.2, 12.5.
-Referring to Instruction 6.4,the last standard normal quantile is _______

Accepted Answer

The answer of Instruction 6.4
The manager of a surveying company...

Question 16

Instruction 6.5
The city manager of a large city believes that the number of reported accidents on any weekend has a normal distribution. She takes a sample of nine weekends and determines the number of reported accidents during each. The ordered array for this data is: 15, 46, 53, 54, 55, 76, 82, 256, 407.
-Referring to Instruction 6.5,the second standard normal quantile is _______

Accepted Answer

The answer of Instruction 6.5
The city manager of a large...

Question 17

Instruction 6.5
The city manager of a large city believes that the number of reported accidents on any weekend has a normal distribution. She takes a sample of nine weekends and determines the number of reported accidents during each. The ordered array for this data is: 15, 46, 53, 54, 55, 76, 82, 256, 407.
-Referring to Instruction 6.5,the first standard normal quantile is _______

Accepted Answer

The answer of Instruction 6.5
The city manager of a large...

Question 18

Instruction 6.4
The manager of a surveying company believes that the average number of phone surveys completed per hour by her employees has a normal distribution. She takes a sample of 15 days' output from her employees and determines the average number of surveys per hour on these days. The ordered array for this data is: 10.0, 10.1, 10.3, 10.5, 10.7, 11.2, 11.4, 11.5, 11.7, 11.8, 11.8, 12.0, 12.2, 12.2, 12.5.
-Referring to Instruction 6.4,the ninth standard normal quantile is_______

Accepted Answer

The answer of Instruction 6.4
The manager of a surveying company...

Question 19

Instruction 6.4
The manager of a surveying company believes that the average number of phone surveys completed per hour by her employees has a normal distribution. She takes a sample of 15 days' output from her employees and determines the average number of surveys per hour on these days. The ordered array for this data is: 10.0, 10.1, 10.3, 10.5, 10.7, 11.2, 11.4, 11.5, 11.7, 11.8, 11.8, 12.0, 12.2, 12.2, 12.5.
-Referring to Instruction 6.4,the fourteenth standard normal quantile is _______

Accepted Answer

The answer of Instruction 6.4
The manager of a surveying company...

Question 20

Instruction 6.5
The city manager of a large city believes that the number of reported accidents on any weekend has a normal distribution. She takes a sample of nine weekends and determines the number of reported accidents during each. The ordered array for this data is: 15, 46, 53, 54, 55, 76, 82, 256, 407.
-Referring to Instruction 6.5,the seventh standard normal quantile is _______

Accepted Answer

The answer of Instruction 6.5
The city manager of a large...

Quiz 6: The Normal Distribution and Other Continuous Distributions

The true length of boards cut at a mill with a listed length of 3 metres is normally distributed with a mean of 303 cm and a standard deviation of 1 cm.What proportion of the boards will be between 301 and 304 cm?

When constructing a normal probability plot,the Z values are plotted on the vertical axis and the corresponding values of the variable are plotted on the horizontal axis.

If a data batch is approximately normally distributed,its normal probability plot would be S-shaped.

A normal probability plot may be used to assess the assumption of normality for a particular batch of data.

The amount of pyridoxine (in grams)in a multiple vitamin is normally distributed with μ = 110 grams and σ = 25 grams.Approximately 83% of the vitamins will have at least how many grams of pyridoxine?