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2 years ago

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The heights of students in a class are normally distributed with mean 55 inches and standard deviation 5 inches. Use the Empiric

al Rule to determine the interval and contains the middle 68% of the heights.
a) [40,70]

b)[45,70]

c)[50,60]

d)[45,65]

e)[47,63]

d)none of the above

1 answer:

maks197457 [2]2 years ago

4 0

Answer: c)[50,60]

Step-by-step explanation:

The Empirical rule says that , About 68% of the population lies with the one standard deviation from the mean (For normally distribution).

We are given that , The heights of students in a class are normally distributed with mean 55 inches and standard deviation 5 inches.

Then by Empirical rule, about 68% of the heights of students lies between one standard deviation from mean.

i.e. about 68% of the heights of students lies between $\text{Mean}\pm\text{Standard deviation}$

i.e. about 68% of the heights of students lies between $55\pm5$

Here, $55\pm5=(55-5, 55+5)=(50,60)$

i.e. The required interval that contains the middle 68% of the heights. = [50,60]

Hence, the correct answer is c) (50,60)

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Answer:

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Step-by-step explanation:

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