Y1 and Y2 denote the proportions of time that employees I and II actually spent working on their assigned tasks during a workday. The joint density of Y1 and Y2 is given. 0, elsewhere
Employee I has a higher productivity rating than employee II and a measure of the total productivity of the pair of employees is 25Y1 + 20Y2. Find the variance of this measure of productivity. (Round your answer to two decimal places.)
Use Tchebysheff's theorem to give an interval in which you think the total productivity measures of the two employees should lie for at least 75% of the days in question. (Round your answers to two decimal places.)
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