# Random Variable and Previous Work Experience

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Business Statistics, ISOM2500 (L3, L4 & L5)
Practice Quiz I
1. The following bar chart describes the results of a survey concerning the relevance of study to present job by school.

Focus on the School of Business and Management. What are the mode and the median respectively?
(a) Relevant, Neutral
(b) Relevant, Relevant
(c) Neutral, Relevant
(d) Neutral, Neutral
2-4. The manager of a specialty outdoor store has gathered the following data concerning sales (in hundreds of dollars) of all the items sold by the store in the previous 2 months:
Item Type pants and jackets hats and gloves socks and shoes skiing hardware climbing hardware

Number sold
150
30
75
25
70

Sales \$(00s)
125
15
400
65
45

2. Using the data along with appropriate computations, which of the following could not be constructed?
(a) A relative frequency table based on the numbers sold of diﬀerent item types.
(b) A pie chart for the percentages of sales of diﬀerent item types.
(c) A bar chart for the sales of hardware for each of the two months.
(d) A Pareto chart for the sales of diﬀerent item types.
3. What is the percentage of dollar sales for hardware?
(a) 16.9%

(b) 27.1%

(c) 10%

(d) 6.9%

4. Which of the following would be the best choice for showing the share of sales due to each Item
Type?
(a) Mode

(b) Median

(c) Frequency table

1

(d) Relative frequency table

5. Two treatments for kidney stones are compared. The following table summarizes their respective successive rate for treatments involving both small and large kidney stones

Small Stones
Large Stones

Treatment A
93%
73%

Treatment B
87%
69%

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