document.write( "Question 444681: In one hour, Steve drives 25 miles farther in his car than John can cycle on his bike. If it takes John an hour and a half hours longer to cycle seventy five miles than it takes Steve in his car, how fast can John cycle? \n" ); document.write( "
Algebra.Com's Answer #306727 by ankor@dixie-net.com(22740)\"\" \"About 
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In one hour, Steve drives 25 miles farther in his car than John can cycle on his bike.
\n" ); document.write( "If it takes John an hour and a half hours longer to cycle seventy five miles than it takes Steve in his car, how fast can John cycle?
\n" ); document.write( ":
\n" ); document.write( "Let c = speed that John can cycle
\n" ); document.write( "Let d = speed Steve can drive
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\n" ); document.write( "Write a distance equation for the statement:
\n" ); document.write( "\"In one hour, Steve drives 25 miles farther in his car than John can cycle on his bike. \"
\n" ); document.write( "Steve's dist - John's dist = 25
\n" ); document.write( "1d - 1c = 25
\n" ); document.write( "d = (c + 25)
\n" ); document.write( ":
\n" ); document.write( "Write a time equation for the statement, (time = dist/speed):
\n" ); document.write( "\"If it takes John an hour and a half hours longer to cycle seventy five miles than it takes Steve in his car,\"
\n" ); document.write( "John's travel time - Steve's travel time = 1.5 hrs
\n" ); document.write( "\"75%2Fc\" - \"75%2Fd\" = 1.5
\n" ); document.write( ":
\n" ); document.write( "Replace s with (c+25)
\n" ); document.write( "\"75%2Fc\" - \"75%2F%28%28c%2B25%29%29\" = 1.5
\n" ); document.write( ":
\n" ); document.write( "Multiply by c(c+25), results
\n" ); document.write( "75(c+25) - 75c = 1.5c(c+25)
\n" ); document.write( "75c + 1875 - 75c = 1.5c^2 + 37.5c
\n" ); document.write( ":
\n" ); document.write( "Arrange as a quadratic equation
\n" ); document.write( "1.5c^2 + 37.5c - 1875 = 0
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\n" ); document.write( "Get rid of those decimals, multiply by 2
\n" ); document.write( "3c^2 + 75c - 3750 = 0
\n" ); document.write( ":
\n" ); document.write( "You can solve this using the quadratic formula, but this will factor to
\n" ); document.write( "(3c + 150)(c - 25) = 0
\n" ); document.write( ":
\n" ); document.write( "The positive solution
\n" ); document.write( "c = 25 mph is the cycling speed
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\n" ); document.write( "To check this; find the driving speed
\n" ); document.write( "d = c+25
\n" ); document.write( "d = 50 mph
\n" ); document.write( "Find the time of each
\n" ); document.write( "75/25 = 3 hrs
\n" ); document.write( "75/50 = 1.5
\n" ); document.write( "---------------
\n" ); document.write( "differ: 1.5 hrs\r
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