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To find:
The mean,
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Answer to Problem 15E
Solution:
The mean age is 36.7 years, the median age is 32 years, and the data is multimodal with modal ages 29 years, 31 years, and 32 years.
Explanation of Solution
Given information:
The given data set is,
Ages of 20 Americans entrepreneurs (in years)
Definition:
Mean is the average of the given data set.
Median is the mid value of ordered data set.
Mode is the most frequently occurred value in the ordered data set.
If all the data values occur only once, then the data set has no mode. If only one value occurs most often, then the data set is unimodal. If exactly two values occur equally often, then the data set is bimodal. If more than two values occur equally often, then the data set is multimodal.
Formula used:
The formula to calculate the mean of set of data is,
Where,
Calculation:
Substitute
Here number of data in the given data set is 20, substitute 20 for
Mean age is 36.7 years.
Formula used:
The formula to calculate the median of set of ordered data is,
Calculation:
Here given set of data is,
Arrange the given data in increasing order.
Number of values in data set is 20, it is even.
Substitute 20 for
Simplify further,
The median age is 32 years.
The most frequently occurred data is the mode.
Here, each of the data 29, 31, 32 occur 2 times.
Modes of the given data set are 29 years, 31 years, and 32 years.
3 data occur most often, so the data set is multimodal.
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Chapter 3 Solutions
Beginning Statistics, 2nd Edition
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