document.write( "Question 117047: A bicyclist rode into the country for 5 hr. In returning, her speed was 5 mi/h faster and the trip took 4 hr. What was her speed each way? \n" ); document.write( "
Algebra.Com's Answer #85148 by bucky(2189) ![]() You can put this solution on YOUR website! Use the equation: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "for the two parts of this problem. D represents the distance traveled, R the rate or speed \n" ); document.write( "of the travel, and T the time spent traveling. \n" ); document.write( ". \n" ); document.write( "For the first part of the problem, call the unknown rate of travel S (standing for speed). And the \n" ); document.write( "problem tells you that the bicyclist rode out into the country for a time T equal to 5 hours. \n" ); document.write( "Putting these values into the Distance equation results in: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "On the return trip the Rate is S + 5 because you are told that it is 5 miles per hour faster \n" ); document.write( "than on the ride out into the country. You are also told that the duration of the return \n" ); document.write( "ride is 4 hours. Putting these values into the Distance equation for the return ride results in: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "Do the distributed multiplication on the right side by multiplying the 4 times each of the \n" ); document.write( "two terms in the parentheses. This multiplication results in the Distance equation becoming: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "Now recognize that the two distances ... the one going into the country and the one returning \n" ); document.write( "are equal. So the right sides of the two Distance equations must be equal. In equation form \n" ); document.write( "this is represented as: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "Get rid of the 4S on the right side by subtracting 4S from both sides. Subtracting 4S \n" ); document.write( "from both sides reduces the equation to: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "This tells us that the bicyclist rode at a speed of 20 miles per hour going out into the country, \n" ); document.write( "and, since the rate or speed was 5 miles per hour faster on the return trip, the speed on \n" ); document.write( "the return trip was 25 miles per hour. \n" ); document.write( ". \n" ); document.write( "And as add information (not required by the problem) the distance she rode into the country \n" ); document.write( "can be determined by multiplying her speed of 20 miles per hour on the outbound trip by the 5 hours \n" ); document.write( "she spent on this portion of the trip. 20 times 5 is 100 miles. On the return trip she rode \n" ); document.write( "at a speed of 25 miles per hour for hours, and 25 times 4 also equals 100 miles, just as it is \n" ); document.write( "supposed to since the distances are equal in both directions. \n" ); document.write( ". \n" ); document.write( "Hope this helps you to understand the problem a little better and helps you to understand the \n" ); document.write( "equation that says Distance equals Rate times Time. \n" ); document.write( ". \n" ); document.write( " |