The number of large cracks in a length of pavement along a certain street has a Poisson distribution with a mean of 1 crack per 100 m. a. What is the probability that there will be exactly 8 cracks in a 500 m length of pavement? b. What is the probability that there will be no cracks in a 100 m length of pavement? c. Let T be the distance in meters between two successive cracks. What is the probability density function of T ? d. What is the probability that the distance between two successive cracks will be more than 50 m?

Statistics 201 9/06/16 Dispersion spread Info about location (avg or median) Range difference between max and min Range=maxmin Positive/right skew mean is pulled to the right, and is larger than the median Negative/left skew mean is pulled to the left, and is smaller than the median Symmetric/bell shaped mean is approximately the same as median IQR= Q Q3 1 is not effected by extreme values b/c os ca;culated using values that lie close to the center of the data set. IQR is not used in inferential statistics but are useful as descriptive statist