The standard deviation of a population is known to be 7.8. If the sample size is 85, what is the standard error of the mean?

Mathematics

2 answers:

barxatty [35]3 years ago

5 0

0.85. My be this is the answer

Nata [24]3 years ago

3 0

Answer: b. 0.85

Step-by-step explanation:

The formula to calculate the standard error is given by :-

$S.E.=\dfrac{\sigma}{\sqrt{n}}$

We are given that the standard deviation of a population : $\sigma = 7.8$

The sample size = 85

Therefore. the standard error of the mean is given by :-

$S.E.=\dfrac{7.8}{\sqrt{85}}=0.846028785493\approx0.85$

Hence, the standard error of the mean = 0.85

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