A trucking company determined that the distance traveled pertruck per year is normally? distributed, with a mean of 70 thousandmiles and a standard deviation of 12 thousand miles. Completeparts? (a) through? (c) below.
a. What proportion of trucks can be expected totravel between 53 and 70 thousand miles in a? year? (Round to fourdecimal places as? needed.)
| b. What percentage of trucks can be expected totravel either less than 75 or more than 110 thousand miles in a?year? (Round to four decimal places as needed.) |
| c. How many miles will be traveled by at least85?% of the?trucks? (Round to two decimal places as needed.) |
