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)\"\" \"About 
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Use the equation:
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\n" ); document.write( "\"D+=+R%2AT\"
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\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.
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\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:
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\n" ); document.write( "\"D+=+S%2A5\"
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\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:
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\n" ); document.write( "\"D+=+%28S+%2B+5%29%2A4\"
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\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:
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\n" ); document.write( "\"D+=+4S+%2B+20\"
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\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:
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\n" ); document.write( "\"5S+=+4S+%2B+20\"
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\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:
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\n" ); document.write( "\"S+=+20\"
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\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.
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\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.
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\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.
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