Probability & Statistics

Syllabus   Notes (Prob.)       Notes (Stat.)     Stat Homework    Prob Homework (1, 2, 3, 4, 5, 6, 7, 8, 9, 10)

Two Problems on the application of Cebysheff's Inequality:

1.  The daily production of electric motors at a certain factory averaged 120, with a standard deviation of 10. 

        a) What can be said about the fraction of days on which the production level falls between 100 and 140?

        b) Find the shortest interval certain to contain at least 90% of the daily production levels.

2.  When a certain speed control device is set at m miles per hour, the actual speed in miles per hour of an   automobile equipped with the device is a random variable with mean of equal to m and standard deviation 3. If the device is set at 45 miles/hour in a zone with speed limit 50 miles/hours, what is the probability that the speed of the car will exceed the speed limit?