Question

This table presents total distance covered, recorded as values and the total number of days as total observations for standard deviation calculation.

Value 3 4 5
Total Observations 2 3 2
Charles records the number of miles he walks every day. The chart includes how many days he walked the given number of miles for one week. Calculate the standard deviation for the number of miles he walked. Round the answer to the nearest hundredth.

(1 point)

0.39

0.57

0.76

0.94

Answer 1

Mean = (3·2 + 4·3 + 5·2)/7 = 28/7 = 4.
Variance = [2(3−4)^2 + 3(4−4)^2 + 2(5−4)^2]/7 = (2·1 + 3·0 + 2·1)/7 = 4/7 ≈ 0.5714.
Standard deviation = sqrt(4/7) ≈ 0.7559 ≈ 0.76.

Answer: 0.76.