bj

and (4.10) - Vera + bx) - bude so that the standard deviation of Y is Oy - blax 30 Example 4.5 Total Project Cost (Computations for Functions of Random Variables) A contractor is interested in the total cost of a project on which she intends to bid. She estimates that materials will cost $25,000 and that her labor will be $900 per day. If the project takes X days to complete, the total labor cost will be 900X dollars, and the total cost of the project (in dollars) will be as follows: C = 25,000 + 900X Using her experience the contractor forms probabilities (Table 4.4) of likely comple- tion times for the project. a. Find the mean and variance for completion time X b. Find the mean, variance, and standard deviation for total cost C Table 4.4 Probability Distribution for Completion Times 10 11 12 13 14 COMPLETION TIME DAYS) Probability 01 03 03 02 01 Zoom: Q Address Links Desktop Local Disk (D:) Prise OX OS FIL