quiz7-key

quiz7-key - Quiz 7. March 23, 2011 Seat # _ Name: _ <...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
Quiz 7. March 23, 2011 Seat # _________ Name: ___ < KEY > ___ Closed book and notes. No calculator. From Problem 4--88, Montgomery and Runger, fourth edition. Assume that the distance between major cracks in a highway follows an exponential distribution with a mean of five miles. Assume that these distances are independent of each other. That is, the cracks occur according to a Poisson process. 1. (3 points) Determine the probability that there is no major crack in a randomly selected 10-mile stretch of highway. ____________________________________________________________ Let X denote the distance to the next major crack. Then X has an exponential distribution with mean 1 / λ = 5 cracks per mile. Therefore, P( X > 10) = 1 P( X 10) = 1 F X (10) = e (10)(1 / 5) = e 2 ____________________________________________________________ 2. (1 points) Determine the standard deviation of the distance between cracks. (Include the units)
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.
Ask a homework question - tutors are online