QRB 501 Final Exam

1) Write the following as an algebraic expression using x as the variable: Five more than the product of 7 and a number 
A. 7x + 5
B. 5 + 7 + x
C. 12x
D. 5 + 7 ÷ x

2) Write the following as an algebraic expression using x as the variable: The sum of a number and -8 
A. -8 + x
B. x(-8) 
C. -8x
D. -8 - x

3) Write the following as an algebraic expression using x as the variable: Triple a number subtracted from the number 
A. x - 3x
B. 3x - x
C. 3(x - x)
D. x 3 – x

4) Solve: –9 + 18 ÷ –3(–6) 
A. 27
B. -0.5
C. 0.5
D. 90

5) Solve: 3(32) – 8(9 – 2) ÷ 2
A. -1
B. 66.5
C. -14.5
D. 55

6) Solve: -3 – (-2 + 4) - 5 
A. -10
B. -6
C. 15
D. 10

7) Identify the variable, constant, and coefficient of the expression: 10k – 15 
A. variable: k; constant: 15; coefficient: 10
B. variable: 15; constant: 10; coefficient: k
C. variable: k; constant: –15; coefficient: 10
D. variable: 10; constant: k; coefficient: –15

8) Identify the variable, constant, and coefficient of the expression: xy 
A. variable: x and y; constant: 0; coefficient: 1
B. variable: y; constant: 0; coefficient: x 
C. variable: x; constant:0; coefficient: y
D. variable: x and y; constant: 0; coefficient: 0

9) Identify the variable, constant, and coefficient of the expression: x – y 
A. variable: x and y; constant: 0; coefficient: 1
B. variable: y; constant: x; coefficient: 0
C. variable: x and y; constant: 0; coefficient: 0
D. variable: x; constant: –y; coefficient: 1 

10) Solve the system of equations: 3x + 2y = 18, y = 3x
A. { (2,6) }
B. { (1,3) }
C. { (4,3) }
D. { (3,9) }

11) Solve the system of equations:
3x – 5y = 7
2x + 3y = 30
A. { (9,4) }
B. { (–1,–2) }
C. { (6,1) }
D. { (3,8) }

12) Solve the system of equations:
4x + 3y = 1
3x + 2y = 2
A. { (4,–5) }
B. { (–1,2) }
C. { (1,–1) }
D. { (–2,3) } 

13) Which of the following is true of an index? 
A. It shows a percent change from one period to another
B. It cannot assume negative values
C. It must be larger than 100
D. It can employ qualitative data

14) Which of the following is a reason for computing an index? 
A. To express a change in unlike items
B. To project future sales
C. To organize similar data
D. To compare base periods

15) Which is true about reporting the Consumer Price Index (CPI)? 
A. It is reported bi-annually
B. It reports all commercial prices
C. It is reported by the Bureau of Labor Statistics
D. It is reported by the Federal Reserve

16) The monthly incomes for a group of engineers are: $2,200, $2,400, $2,600, $3,100, $3,400, and $3,700. What are these ungrouped numbers called? 
A. Histograms
B. Class frequencies
C. Class limits
D. Raw data

17) Why are unequal class intervals sometimes used in a frequency distribution? 
A. To avoid a large number of empty classes
B. To create variety in presenting the data
C. To avoid the need for midpoints
D. To make the class frequencies smaller

18) On which axis is time plotted on a simple line chart? 
A. On the X-axis
B. On the Y-axis
C. Time is not plotted
D. Either axis

19) What is the slope of the line: 5y – x = 10 
A. 1/5
B. 2
C. -1
D. 1/2

20) What is the slope of the line: 2y + 8x = 26 
A. -4
B. 8
C. 1/4
D. 2

21) What is the slope of the line: 36x – 9y = 15 
A. 4
B. 36
C. 3
D. -5/3

22) Which statement is true of the y-intercept in the linear regression model? 
A. It is always zero.
B. It is always a positive value.
C. The value depends on the slope of the line.
D. It may be any value.

23) Which statement is true regarding the estimated slope of a linear regression line? 
A. It shows the change in x for a unit change in y.
B. It is chosen so as to minimize the sum of squared errors.
C. It is always positive.
D. It could curve up or down as it moves to the right.

24) Which statement is true of a regression line that is superimposed on the scatter plot? 
A. It is computed using the Ordinary Least Squares method.
B. It guarantees the largest possible sample variance.
C. It is computed using the maximum and minimum values.
D. It guarantees that the slope and intercept are minimized.

25) When the interest rate is positive, what happens to the value of money as we move from the future to the present? 
A. Increases
B. Stays the same
C. Not enough information
D. Decreases

26) How much money would we need to pay off a $2,000 loan at 8% interest, 4 years from now? 
A. $2,721
B. $1,978
C. $2,632
D. $3,220

27) What happens to the future value of money when the inflation rate exceeds the interest rate? 
A. Increases
B. Decreases
C. Not enough information
D. Stays the same

28) What does the horizontal axis of a line chart represent? 
A. Dollars
B. Time
C. Percent
D. Variable quantity

29) How is a frequency distribution converted to a relative frequency distribution? 
A. Find the difference between consecutive lower class limits.
B. Divide the class frequency by the total number of observations
C. Multiply the class frequency by 100
D. Divide the lower limit of the first class by the class interval

30) What is class frequency? 
A. The number of observations in each class
B. The difference between consecutive lower class limits
C. Usually a multiple of the lower limit of the first class
D. Always contains at least 5 observations

31) What is the relationship among the mean, median, and mode in a symmetric distribution? 
A. All are equal
B. Mean is the smallest value
C. Mode is the largest value
D. Mean is the largest value

32) What is a disadvantage of using range as a measure of dispersion? 
A. Range can be distorted by a large mean.
B. Range is not in the same units as the original data.
C. Range is based on only two observations.
D. Range is too broad.

33) For which measure of central tendency will the sum of the deviations always be zero? 
A. Mode
B. Median
C. Mean
D. Mode and Median

34) Which of the following is true in a normal distribution? 
A. Mean is not equal to the mode or the median.
B. Mean divides the distribution into two unequal parts.
C. Mode equals the median.
D. The curve stops at plus or minus 3 standard deviations.

35) Which of the following is true regarding the normal distribution? 
A. Mean, median and mode are all equal
B. It is not always symmetrical
C. It can have more than one peak
D. The total area under the curve is greater than 1

36) What percentage of observations of a normal distribution is represented by the mean plus or minus 1.96 standard deviations? 
A. 99.7
B. 68%
C. 95%
D. 100%