Download True/false and multiple choice

Quiz #1E
Semester 061
Dept of Mathematical Sciences
Stat319: Intro to Prob & Stat for Engineers & Scientists
Instructor: Dr. Mohammad H. Omar
Section: 1 (8-8.50am), 3 (9-9.50am), or 6(11-11.50am)
Name:_______________________ ID#:______________ Serial #:_____________________
Directions: This quiz is designed for 45 minutes. Please answer all questions
True/false and multiple choice (circle the best answer)
1. A histogram can be constructed for data that are either quantitative or qualitative.
(True/False)
2. One of the differences between a stem & leaf diagram and a histogram is that even for variables
involving a large number of different values, the stem & leaf diagram shows the individual data
values whereas the histogram requires you to group the data and lose the individual values.
(True/False)
3. A study was recently conducted in which makers of toothpaste tracked sales for the month at
different stores in a market area. The variable of interest was the number of units sold. The
numbers ranged from 1,200 to 22,700. In this case, the stems in a stem & leaf diagram might be
values such as 1 and 22 while the leaves would be 200 and 700.
(True/False)
4. Which of the following is an acceptable format for setting up class boundaries for a frequency
distribution?
a. 20 and under 40
b. 20 – 40
c. 200 – 299.99
d. All of the above.
5. If after graphing the data for a quantitative variable of interest, you notice that the distribution is
highly skewed in the positive direction, the measure of central location that would likely provide
the best assessment of the center would be the median.
(True/False)
6. A distribution is said to be symmetric when the sample mean and the population mean are equal.
(True/False)
Solving Questions (show your calculations and final answer)
7. The credit card balances for customers at State Bank and Trust has a mean equal to $800 and a
standard deviation equal to $60.00. Kevin Smith’s balance is $1,352. Based on this, find his
standardized value (z-score).
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Quiz #1E
Semester 061
Dept of Mathematical Sciences
Stat319: Intro to Prob & Stat for Engineers & Scientists
Instructor: Dr. Mohammad H. Omar
Section: 1 (8-8.50am), 3 (9-9.50am), or 6(11-11.50am)
Name:_______________________ ID#:______________ Serial #:_____________________
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Directions: This quiz is designed for 45 minutes. Please answer all questions
8. The following data reflect the number of customers who return merchandise for a refund on
Monday. Note these data reflect the population of all 10 Mondays for which data are available.
Based on these data, calculate the standard deviation.
9. The number of days that houses stay on the market before they sell in Houston is bell-shaped with
a mean equal to 56 days. Further, 95 percent of all homes are on the market between 40 and 72
days. Based on this information, find the standard deviation for the number of days that houses
stay on the market in Houston.
10. The AMI Company has two assembly lines in its Kansas City plant. Line A produces an average
of 335 units per day with a standard deviation equal to 11 units. Line B produces an average of
145 units per day with a standard deviation equal to 8 units. Based on this information, which line
is relatively more consistent?
11. The following sample data reflect electricity bills for ten households in San Diego in March.
Determine three measures of central tendency for these sample data. Then, based on these
measures, determine whether the sample data are symmetric or skewed.
Quiz #1E
Semester 061
Dept of Mathematical Sciences
Stat319: Intro to Prob & Stat for Engineers & Scientists
Instructor: Dr. Mohammad H. Omar
Section: 1 (8-8.50am), 3 (9-9.50am), or 6(11-11.50am)
Name:_______________________ ID#:______________ Serial #:_____________________
Directions: This quiz is designed for 45 minutes. Please answer all questions
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