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(a)
To find: The given variable is sample proportion or population proportion.
(a)
Answer to Problem 10.1E
The value is population proportion.
Explanation of Solution
Given information:
It is mentioned in the census of 1990 that one out of nine individuals of country A were at least 65 years or older.
Concept used:
The whole collection or group of all the elements is known as the population. The sample is the group of elements collected from the population and has similar characteristics to the population.
An official count of the population is known as the census.
Proportion value calculated from the sample is sample proportion and calculated from the population is population proportion.
In this case, the census results suggest that one out of nine individuals of country A were at least 65 years or older. This percentage value is observed from the census that is based on the population. As this proportion value is measured from the entire population of country A, it is considered a population proportion.
Hence, the desired answer is population proportion.
(b)
To find: The given variable is sample proportion or population proportion.
(b)
Answer to Problem 10.1E
The value is the sample proportion.
Explanation of Solution
Given information:
The proportion is calculated from the sample of 500 voters.
In this case, the results were collected from 500 adults. This percentage value is observed from the sample of 500 individuals. As this proportion value is measured from the part of the population, not from the complete population, it is considered a sample proportion.
Hence, the desired answer is sample proportion.
(c)
To find: The given variable is sample proportion or population proportion.
(c)
Answer to Problem 10.1E
The value is the sample proportion.
Explanation of Solution
Given information:
The proportion of 55% is calculated from the sample of 80 individuals.
In this case, the results were collected from 80 individuals. This percentage value of 55% is observed from the sample of 80 individuals. As this proportion value is measured from the part of the population, not from the entire population, it is considered a sample proportion.
Hence, the desired answer is sample proportion.
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Chapter 10 Solutions
Mind on Statistics
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