Question

Thickness measurements of a coating process are made to the nearest hundredth of a millimeter. The thickness measurements are uniformly distributed with values 0.13, 0.14, 0.15, 0.16, 0.17. Determine the mean and variance of the coating thickness for this process. Round your answers to four decimal places (e.g. 98.7654).

Answer 1

Answer:

Mean=0.1500mm

Variance=0.00025mm

Explanation:

The discrete uniform distribution has parameters

a=13 and b=17

Calculating the mean:

$E(x)=\frac{13+17}{2}\\ E(x)=15*10^{-2}mm\\ or\\E(x)=0.1500mm$

For variance

$Var(x)=\frac{(17-13+1)^{2} -1}{9.5}\\Var(x)=2.5*10^{-4}mm\\ or\\Var(x)=0.00025mm$