Question

The lengths of plate glass parts are measured to the nearest tenth of a millimeter. the lengths are uniformly distributed with values at every tenth of a millimeter starting at 590.2, and continuing through 590.8. determine the mean and variance of the lengths.

Answer 1

The values are:

590.2, 590.3, 590.4, 590.5, 590.6, 590.7, 590.8

 

Calculating for the mean:

mean = (590.2 + 590.3 + 590.4 + 590.5 + 590.6 + 590.7 + 590.8) / 7

mean = 590.5

 

The variance:

variance = [(590.2-590.5)^2 + (590.3-590.5)^2 + (590.4-590.5)^2 + (590.5-590.5)^2 + (590.6-590.5)^2 + (590.7-590.5)^2 + (590.8-590.5)^2] / 6

variance = 0.047