During a trip on an expressway, Don drove a total of x miles. His average speed on a certain 5-mile section of the expressway was 30 miles per hour, and his average speed for the remainder of the trip was 60 miles per hour. His travel time for the x-mile trip was what percent greater than it would have been if he had traveled at a constant rate of 60 miles per hour for the entire trip?	Options.
A) 8.5%	B) 50%	C) x/12%	D) 60/x%	E) 500/x%
total dist = x miles   time take to clear 5 mile section at 30 miles/hr = 5/30 = 1/6 hr   time taken to clear x-5 miles section at 60 miles/hr = x-5/60 hr   Total time = 1/6 + x-5/60 = x+5/60 hr   Total time to clear x miles if he traveled at constant rate of 60 miles/hr = x/60 hr   500/x%xtra time = 5/60 = 1/12 hr   Percentage greater = (1/12)/(x/60) * 100% = 500/x %   ANSW500/x%R:500/x%
<result>E</result>
During a trip on an expressway, Don drove a total of x miles. His average speed on a certain 5-mile section of the expressway was 30 miles per hour, and his average speed for the remainder of the trip was 60 miles per hour. His travel time for the x-mile trip was what percent greater than it would have been if he had traveled at a constant rate of 60 miles per hour for the entire trip?