MATH 533 Week 8 Final Exam Set 3 A GRADED

Answer The length of time to do a cable installation by Multi-Cable Inc. is normally distributed with a mean of 42.8 minutes & a standard deviation of 6.2 minutes. What percentage of installations take less than 30 minutes? x = The length of time to do a cable installation  = 42.8  = 6.20 z = x -   P(x 30) = P(z -2.06) = 0.5 - 0.4803 = 0.0197 or 1.97% Answer Accident claims are checked for completeness by branch offices of Fortune Insurance before they are sent to a regional office for payment. Historically 80% of the claims are complete when they reach the regional office. You select a random sample of 20 claims that have arrived at the regional office. Find the probability that: X = Number of completed forms in sample n = 20 p = 0.80 a. At least 16 claims are complete, P(X  16) = P(X = 16) + … + P(X = 20) = 0.6296 b. All 20 are complete, P(X = 20) = 0.0115 c. Fewer than 12 are complete