finite Math 200 Question Help

5. [-/2 Points] DETAILS TANFIN12 8.6.006. MY NOTES PRACTICE ANOTHER The tread lives of the Super Titan radial tires under normal driving conditions are normally distributed with a mean of 60,000 mi and a standard deviation of 5000 mi. (Round your answers to four decimal places.) What is the probability that a tire selected at random will have a tread life of more than 55,250 mi? Determine the probability that four tires selected at random still have useful tread lives after 55,250 mi of driving. (Assume that the tread lives of the tires are independent of each other.) You may need to use the appropriate table in the Appendix of Tables to answer this question. Need Help? Read it Watch It 6. [-/1 Points] DETAILS TANFIN12 8.6.008. MY NOTES PRACTICE ANOTHER To be eligible for further consideration, applicants for certain civil service positions must first pass a written qualifying examination on which a score of 80 or more must be obtained. In a recent examination, it was found that the scores were normally distributed with a mean of 70 points and a standard deviation of 10 points. Determine the percentage of applicants who passed the written qualifying examination. (Round your answer to two decimal places.) You may need to use the appropriate table in the Appendix of Tables to answer this question. Need Help? Read It 7. [-/1 Points] DETAILS TANFIN12 8.6.010. MY NOTES PRACTICE ANOTHER The scores on an economics examination are normally distributed with a mean of 78 and a standard deviation of 11. If the instructor assigns a grade of A to 15% of the class, what is the lowest score a student may have and still obtain an A? (Round your answer to two decimal places.) You may need to use the appropriate table in the Appendix of Tables to answer this question. Need Help? Read it Watch It 8. [-/3 Points] DETAILS TANFIN12 8.6.012. MY NOTES PRACTICE ANOTHER The speeds (in miles per hour) of motor vehicles on a certain stretch of Route 3A as clocked at a certain place along the highway are normally distributed with a mean of 64.4 mph and a standard deviation of 5.37 mph. What is the probability that a motor vehicle selected at random is traveling at the following speeds? (Round your answers to four decimal places.) (a) more than 66 mph (b) less than 62 mph (c) between 66 and 71 mph You may need to use the appropriate table in the Appendix of Tables to answer this question. Need Help? Read It 9. [-/3 Points] DETAILS TANFIN12 8.6.002. MY NOTES PRACTICE ANOTHER According to the data released by the Chamber of Commerce of a certain city, the weekly wages of factory workers are normally distributed with a mean of $770 and standard deviation of $50. Find the probability that a worker selected at random from the city makes the following weekly wage. (Round your answers to four decimal places.) (a) less than $770 (b) more than $905 (c) between $620 and $820 You may need to use the appropriate table in the Appendix of Tables to answer this question. Need Help? Read It 10. [-/1 Points] DETAILS TANFIN12 8.6.007. MY NOTES PRACTICE ANOTHER According to the data released by the Chamber of Commerce of a certain city, the weekly wages (in dollars) of female factory workers are normally distributed with a mean of 600 and a standard deviation of 50. Find the probability that a female factory worker selected at random from the city makes a weekly wage of $570 to $705. (Round your answer to four decimal places.)