Type the correct answer in the box.

Helen gathered data on the fuel efficiency of compact sedans. Her sample contains 80 data points, and the standard error of the mean is approximately 0.595.

What is the standard deviation? Round your answer to the nearest hundredth.

The standard deviation is approximately _____.



Answer :

To find the standard deviation from the given standard error and sample size, we can follow these steps:

1. Understand the Relationship: Recall that the standard error (SE) of a sample mean is related to the standard deviation (SD) of the sample by the formula:
[tex]\[ SE = \frac{SD}{\sqrt{n}} \][/tex]
where [tex]\( n \)[/tex] is the sample size.

2. Rearrange the Formula: To find the standard deviation, rearrange the formula to solve for [tex]\( SD \)[/tex]:
[tex]\[ SD = SE \times \sqrt{n} \][/tex]

3. Substitute the Given Values:
- The sample size [tex]\( n \)[/tex] is 80.
- The standard error [tex]\( SE \)[/tex] is approximately 0.595.

Now, substitute these values into the formula:
[tex]\[ SD = 0.595 \times \sqrt{80} \][/tex]

4. Calculate the Square Root: The square root of 80 is approximately 8.944.

5. Perform the Multiplication: Multiply the standard error by the square root of the sample size:
[tex]\[ SD = 0.595 \times 8.944 \approx 5.321841786449499 \][/tex]

6. Round to the Nearest Hundredth: Finally, round the result to the nearest hundredth (two decimal places):
[tex]\[ SD \approx 5.32 \][/tex]

Therefore, the standard deviation is approximately 5.32.