Q1. Describing Data: Frequency Distribution and Graphic Presentations:
You are the parts manager for a local Dumb Phone Repair Shop. You notice that it is taking more than 10 days for parts to be shipped to your store. Therefore you decide to sample the next 50 orders and track the days it takes from ordering to arrival. Your assistant hands you the following info:
Number of Days from order date to arrival in El Paso.
5 10 12 15 20 3 4 5 1 12
9 19 20 24 16 21 20 15 13 9
5 1 2 3 17 21 14 8 6 21
3 6 7 15 19 5 7 9 22 23
12 11 10 14 16 13 14 10 7 4
a. Determine the Number of Classes
b. Determine the Interval of Classes
c. Construct a frequency distribution using the following format
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Classes
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Tally
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Frequency(f)
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Cumulative Frequency (Cf)
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d. Use graph paper or an excel program to plot the Histogram for this data.
e. On a separate graph draw and label the Cumulative Frequency Polygon.
Q2. Describing Data: Measures of Central Tendency
Using the data from the previous question, calculate the following statistics using the frequency distribution table, not the raw data:
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Classes
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Frequency(f)
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midpoint(X)
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fX
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Cf
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a. The midpoint for each class (enter in table above):
b. Calculate the estimated arithmetic mean of the sample
c. Calculate the estimated arithmetic median of the sample
d. The estimated mode of the sample
Q3. Other Descriptive Measures:
A sample of the personnel files of eight employees employed by the Hot SPA & Wine Château revealed that, during a six-month period they lost the following numbers of days due to illness.
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Day Lost (X)
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2
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0
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6
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3
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10
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4
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1
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2
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Calculate the following statistics.
1. Calculate the Variance
2. Calculate the Standard Deviation
3. What does the S D tell us about this data?