List of top Quality and Reliability Questions on Surface Roughness Measurement Techniques

The absolute deviations of 8 points from the datum line of a surface are 10, 15, 12, 10, 13, 12, 20 and 25 μm. The root mean square value of the surface roughness (in μm) is \(\underline{\hspace{2cm}}\) (round off to one decimal place).