Test on Comprehensive Guide to Business Statistics
Comprehensive Guide to Business Statistics for Students
Test: Financial mathematics — Time value & Annuities, Foundations of Statistics, Sampling Theory and Foundations, Sampling Methods and Bias, Statistical Inference & Estimation, Study design, Data collection, Descriptive Statistics & Visualization, Financial mathematics — Loans, Amortization & Sinking Funds, Financial mathematics — Capital Budgeting & Investment Appraisal, Continuous Distributions, Probability Distributions, Measures and Dispersion, Discrete Probability Models, Statistical Tables & Resources, Sampling Distributions and CLT, Sampling, Distributions & Confidence
20 questions
Question 1: In the formula for computing the median of grouped data, the term CF(<) represents the cumulative less than frequency of the class immediately preceding the median class.
A. Yes
B. No
Explanation: The study materials state: "CF(<) = The value of the Cumulative Less Than Frequency of the class PRECEDING the median class." This confirms that the term refers to the CF(<) of the class prior to the median class.
Question 2: Which of the following is identified as a measure of dispersion (or variation) in the provided study materials?
A. The Mean
B. The Median
C. The Range
D. The Mode
Explanation: The study materials state that "Such measures are called measures of dispersion (or variation). The ones that will be discussed in this section are THE RANGE and THE STANDARD DEVIATION." The Mean, Median, and Mode are described as "MEASURES OF CENTRAL LOCATION".
Question 3: The number of occurrences, 'x', in the Poisson probability distribution formula can be a negative integer.
A. Yes
B. No
Explanation: The study materials state that 'x' in the Poisson formula represents the number of occurrences, and $x = 0, 1, 2, 3, \dots$, indicating it can only be a non-negative integer.
Question 4: A small support desk receives calls at an average rate of 5 calls per hour. Based on the Poisson probability distribution, what is the probability that they will receive exactly 2 calls in a 30-minute period?
A. 0.1839
B. 0.2240
C. 0.2565
D. 0.2707
Explanation: The Poisson probability distribution is used for a discrete number of events in a continuous interval. First, we need to determine the average number of occurrences ($\lambda$) for the specified time interval. The average rate is 5 calls per hour. The question asks for the probability in a 30-minute period. Since 30 minutes is half an hour, $\lambda = 5 ext{ calls/hour} \times (0.5 ext{ hour}) = 2.5 ext{ calls}$ per 30-minute period. We need to find $P(X = 2)$ when $\lambda = 2.5$. Consulting Table 10, 'THE POISSON DISTRIBUTION', we look for the column 'm = 2.5' and the row 'x = 2'. The value at this intersection is -2565. Therefore, the probability is 0.2565.
Question 5: The area under the standard normal curve between z = 0 and z = 1.00 is 0.3000.
A. Yes
B. No
Explanation: For a z-score of 1.00, Table I indicates the area under the standard normal curve from 0 to z is 0.3413, not 0.3000.