You are shopping for new tires. You buy a trade magazine that evaluates tires to help you in your decision. Unfortunately you left the magazine on the coffee table and you dog chewed it up. The information on the tires you are interested in was mostly destroyed, but you do find the following information. On one scrap of paper you find that a set of test tires lasted 156,000 km and this was listed as 1.7 standard deviations above the mean. On another piece of paper it lists the variance of tire mileage as 160,000. How long do these tires last on average?