Find the standard deviation of the sample below. Round your answer to the nearest tenth.

• A. 24.7
• B. 3.9
• C. 607.8
• D. 15.5

Answer: (B)

Verified step by step guidance

1. Step 1: Calculate the mean (average) of the sample data. Add all the ages together and divide by the number of ages. The ages are: 24, 27, 30, 23, 20, 19, 21, 18, 25.
2. Step 2: Subtract the mean from each age to find the deviation of each age from the mean. This will give you a list of deviations.
3. Step 3: Square each deviation to eliminate negative values and emphasize larger deviations.
4. Step 4: Calculate the average of these squared deviations. This is known as the variance. Add all the squared deviations together and divide by the number of ages minus one (n-1) since this is a sample.
5. Step 5: Take the square root of the variance to find the standard deviation. This will give you the measure of spread of the ages in the sample.