Question

Calculate the standard deviation of these measurements and plot the frequency distribution.

Measurement no.(i) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15. Diameter d (mm) 1.26 1.26 1.29 1.31 1.28 1.27 1.26 1.25 1.28 1.32 1.21 1.27 1.22 1.29 1.28

Answer 1

$Mean = \frac{1.26 + 1.26 …. 1.29 + 1.28}{15} = 1.27$

Standard deviations

$σ = \sqrt{\frac{1}{15-1} ((1.26-1.27)^2 + (1.26-1.27)^2 +...+ (1.29-1.27)^2 + (1.28-1.27)^2)} = 0.02927$

Frequency distribution