Question 1

When you produce a grouped frequency distribution you lose individual values for x. What method should be used to estimate values of x for each class?

Accepted Answer

A)  You should use the lower limit 
B)  You should use the upper limit 
C)  You should use the class width 
D)  You should use the class midpoint 
A)  You should use the lower limit 
B)  You should use the upper limit 
C)  You should use the class width 
D)  You should use the class midpoint D

Question 2

A vending machine operator knows that her 6 vending machines in a Kuwaiti shopping centre produce an average daily revenue of KWD 125 (Kuwaiti Dinar). She adds a 7th machine that generates an average revenue of KWD 140 (the remaining machines continue to produce the amounts). What is the new average for all her machines?

Accepted Answer

A)  KWD 126.9 
B)  KWD 127.0 
C)  KWD 127.1 
D)  KWD 127.2 
A)  KWD 126.9 
B)  KWD 127.0 
C)  KWD 127.1 
D)  KWD 127.2 C

Question 3

Which of the following statements about the mean IS true?

Accepted Answer

A)  If you have open-ended classes in a grouped frequency distribution is is necessary to determine a nominal limit to the class 
B)  When reporting the value of the mean, is it usual to present the value with the same number of decimal places as the original data 
C)  The sum of deviations from the mean is always the same as the number of data points (frequency) 
D)  The mean is the least used of all the ways of presenting measures of location 
A)  If you have open-ended classes in a grouped frequency distribution is is necessary to determine a nominal limit to the class 
B)  When reporting the value of the mean, is it usual to present the value with the same number of decimal places as the original data 
C)  The sum of deviations from the mean is always the same as the number of data points (frequency) 
D)  The mean is the least used of all the ways of presenting measures of location A

Question 4

A carpet company in Egypt checks orders from the weekend. There were 6 sales (Egyptian Pounds): £8,500; £12,500; £11,000; £24,000; £14,500; and £7,500. Calculate the arithmetic mean of these sales.

Accepted Answer

A)  £11,000 
B)  £12,000 
C)  £13,000 
D)  £14,000 
A)  £11,000 
B)  £12,000 
C)  £13,000 
D)  £14,000

Question 5

The total weight of bags placed on an aircraft is 2730kg. You know that the average weight of each bag is 13.0kg. Assuming every passenger has a bag, how many passengers are there on the plane?

Accepted Answer

A)  200 
B)  210 
C)  220 
D)  230 
A)  200 
B)  210 
C)  220 
D)  230

Question 6

Having collected data on the average order value from 100 customers, which type of statistical measure gives a value which might be used to characterise average value for the whole group?

Accepted Answer

A)  Measure of location 
B)  Measure of reliability 
C)  Measure of dispersion 
D)  Measure of skewness 
A)  Measure of location 
B)  Measure of reliability 
C)  Measure of dispersion 
D)  Measure of skewness

Question 7

The mean number of visitors to a local tourist attraction in the last week was 625 per day. You have the figures for 6 out of 7 days, but the last figure has gone missing. The figures you have are: 800; 950; 425; 570; 725; and 600. Calculate the value of the missing figure.

Accepted Answer

A)  285 
B)  305 
C)  325 
D)  345 
A)  285 
B)  305 
C)  325 
D)  345

Question 8

A pharmaceutical company has sales agents in 4 European countries. Individual average sales figures are [average(number of sales)]: €24,348(23); €17,639(17); €22,902(16); €13,650(21). Calculate the weighted mean for these sales figures.

Accepted Answer

A)  €19648.7 
B)  €19384.8 
C)  €19508.4 
D)  €19709.9 
A)  €19648.7 
B)  €19384.8 
C)  €19508.4 
D)  €19709.9

Question 9

Over the course of an evening, a restaurant collects information about how many diners sit at each table. The data is as follows [number of diners(frequency)]: 1(4); 2(46); 3(16); 4(24); 5(6); 8(1). Calculate the mean number of diners per table.

Accepted Answer

A)  2.7 
B)  2.8 
C)  2.9 
D)  3.0 
A)  2.7 
B)  2.8 
C)  2.9 
D)  3.0

Question 10

Which of the following statements about the mean is NOT true?

Accepted Answer

A)  The mean is generally accepted as being representative of the data 
B)  The mean is a mathematical average calculated from the data 
C)  The mean always takes the same value as one of the original data points 
D)  The mean may not be suitable for data sets that include extremely high or low values 
A)  The mean is generally accepted as being representative of the data 
B)  The mean is a mathematical average calculated from the data 
C)  The mean always takes the same value as one of the original data points 
D)  The mean may not be suitable for data sets that include extremely high or low values

Exam 6: Arithmetic Mean

When you produce a grouped frequency distribution you lose individual values for x. What method should be used to estimate values of x for each class?

Which of the following statements about the mean IS true?

A carpet company in Egypt checks orders from the weekend. There were 6 sales (Egyptian Pounds): £8,500; £12,500; £11,000; £24,000; £14,500; and £7,500. Calculate the arithmetic mean of these sales.

The total weight of bags placed on an aircraft is 2730kg. You know that the average weight of each bag is 13.0kg. Assuming every passenger has a bag, how many passengers are there on the plane?

Having collected data on the average order value from 100 customers, which type of statistical measure gives a value which might be used to characterise average value for the whole group?

The mean number of visitors to a local tourist attraction in the last week was 625 per day. You have the figures for 6 out of 7 days, but the last figure has gone missing. The figures you have are: 800; 950; 425; 570; 725; and 600. Calculate the value of the missing figure.

A pharmaceutical company has sales agents in 4 European countries. Individual average sales figures are [average(number of sales)]: €24,348(23); €17,639(17); €22,902(16); €13,650(21). Calculate the weighted mean for these sales figures.

Over the course of an evening, a restaurant collects information about how many diners sit at each table. The data is as follows [number of diners(frequency)]: 1(4); 2(46); 3(16); 4(24); 5(6); 8(1). Calculate the mean number of diners per table.

Which of the following statements about the mean is NOT true?

Introduction to Business Mathematics and Statistics

Sampling and Data Collection

Data and Their Accuracy

Frequency Distributions and Charts

General Charts and Graphs

Median

Mode and Other Measures of Location

Measures of Dispersion and Skewness

Standard Deviation

Quantiles and the Quartile Deviation

Linear Functions and Graphs

Regression Techniques

Correlation Techniques

Time Series Model

Time Series Trend

Seasonal Variation and Forecasting

Index Relatives

Composite Index Numbers

Special Published Indices

Interest and Depreciation

Present Value and Investment Appraisal

Annuities

Functions and Graphs

Linear Equations

Quadratic and Cubic Equations

Differentiation and Integration

Cost, Revenue and Profit Functions

Set Theory and Enumeration

Introduction to Probability

Conditional Probability and Expectation

Combinations and Permutations

Binomial and Poisson Distributions

Normal Distribution

Linear Inequalities

Matrices

Inventory Control

Network Planning and Analysis

Filters