Question: An Automotive manufacturer removes the friction linings from the clutch plates of drag race cars following test runs. A sample of 10 linings is studied. Measurements for wear showed the following values (in micro meters): 204.5, 231.1, 157.5, 190.5, 261.6, 127.0, 216.6, 172.7, 243.8, 291.0.

Estimate the average wear and its variance. Based on this sample, how many clutch plates out of a large set will be expected to show wear of more than 203 micro meters?