finite Math 200 Question Help

1. [-/3 Points] DETAILS TANFIN 12 8.6.001. MY NOTES PRACTICE ANOTHER The medical records of infants delivered at Kaiser Memorial Hospital show that the infants' lengths at birth (in inches) are normally distributed with a mean of 22 and a standard deviation of 2.6. Find the probability that an infant selected at random from among those delivered at the hospital measures the following. (Round your answers to four decimal places.) (a) more than 23 in. (b) less than 21 in. (c) between 20 and 24 in. You may need to use the appropriate table in the Appendix of Tables to answer this question. Need Help? Read It 2. [-/4 Points] DETAILS TANFIN 12 8.6.003. MY NOTES PRACTICE ANOTHER TKK Products manufactures 50-, 60-, 75-, and 100-watt electric light bulbs. Laboratory tests show that the lives of these light bulbs are normally distributed with a mean of 600 hr and standard deviation of 100 hr. What is the probability that a TKK light bulb selected at random will burn for the following times? (Round your answers to four decimal places.) (a) more than 750 hr (b) less than 450 hr (c) between 600 and 750 hr (d) between 450 and 650 hr You may need to use the appropriate table in the Appendix of Tables to answer this question. Need Help? Read It 3. [-/3 Points] DETAILS TANFIN 12 8.6.004. MY NOTES PRACTICE ANOTHER On average, a student takes 110 words/minute midway through an advanced court reporting course at the American Institute of Court Reporting. Assuming that the dictation speeds of the students are normally distributed and that the standard deviation is 10 words/minute, find the probability that a student randomly selected from the course can take dictation at the following speeds. (Round your answers to four decimal places.) (a) more than 140 words/minute (b) between 100 and 140 words/minute (c) less than 100 words/minute You may need to use the appropriate table in the Appendix of Tables to answer this question. Need Help? Read It 4. [-/4 Points] DETAILS TANFIN 12 8.6.005. MY NOTES PRACTICE ANOTHER The IQs of students at Wilson Elementary School were measured recently and found to be normally distributed with a mean of 110 and a standard deviation of 11. What is the probability that a student selected at random will have the following IQs? (Round your answers to four decimal places.) (a) 140 or higher (b) 115 or higher c) between 110 and 115 (d) 100 or less