Question

5. The mean time for a 100 meter race at a college track meet is 13.2 seconds, with a standard deviation of 0.9 seconds. To win, the next sprinter needs to run the race in 12.5 seconds or less Assuming this random variable is normally distributed, what is the probability of the sprinter running the race in a short enough time to take the lead? 6) A denim company sells its jeans both online and at a retail store. Assume that 80% of the company's sales are retail, and 20% of sales are online. a. What's the probability that all of the next four pairs of jeans are sold online? b. What's the probability that three out of the next four pairs of jeans are sold online? c. Use your answers from parts (a) and (b) to derive a formula for p(x), the probability distribution of the bingmial random variable x, the number of the next four pairs of jeans sold online.

Answer 1

P (x 12.5) 1213.2 PC乙く O.9 O.217-