This can be solved using the formula for t test which is = x - mu over standard deviation divided by the square root of the number of samples. In this case, it is 1185 - 1200 over 70 divided by square root of 100 which give us a value of 2.14 which is equal to .9839 in area. Only rarely, just over one time in a hundred tries of 100 light bulbs, would the average life exceed 1200 hours.
Answer: B - The mean height of all the students of the college.
Explanation:
In statistics, the concept of parameter refers to the value that you want to know about a population to characterize it, for example, mean height, mean age, etc.
In this case, the value that you want to know about the population of the college is the mean height of its students, so the correct option is B.
The following concepts are used in statistics that can be applied to the given example:
- Population (all students of the university).
- Parameter (mean height of university students).
- Sample (the 25 randomly selected students).
- Elements (the heights of the selected students).
- Estimator (average height of randomly selected students).
<u>EXPLANATION</u>
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Step-by-step explanation:
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