document.write( "Question 277650: A man bicycles 5.4 mph faster than he can walk. He bicycles a distance of 32.4 miles and then hikes back along the same route. If the entire trip takes 12.6 hours, how fast does he walk? \n" ); document.write( "
Algebra.Com's Answer #202102 by stanbon(75887)![]() ![]() ![]() You can put this solution on YOUR website! A man bicycles 5.4 mph faster than he can walk. He bicycles a distance of 32.4 miles and then hikes back along the same route. If the entire trip takes 12.6 hours, how fast does he walk? \n" ); document.write( "--------- \n" ); document.write( "Let his walking rate be w mph \n" ); document.write( "Then his biking rate is w+5.4 mph \n" ); document.write( "------------------------------------- \n" ); document.write( "Bike DATA: \n" ); document.write( "distance = 32.4 mi; rate = (w+5.4) mph ; time = d/r = 32.4/(w+5.4)hrs. \n" ); document.write( "--------------------------------------------- \n" ); document.write( "Walk DATA: \n" ); document.write( "distance = 32.4 mi ; rate = w mph ; time = d/r = 32.4/w hrs. \n" ); document.write( "--- \n" ); document.write( "Equation: \n" ); document.write( "time + time = 12.6 hrs \n" ); document.write( "32.4/(w+5.4) + 32.4/w = 12.6 \n" ); document.write( "---- \n" ); document.write( "Multiply thru by 10: \n" ); document.write( "324/(w+5.4) + 324/w = 126 \n" ); document.write( "--- \n" ); document.write( "Multiply thru by w(w+5.4) to get: \n" ); document.write( "324w + 324(w+5.4) = 126w(w+5.4) \n" ); document.write( "--- \n" ); document.write( "648w + 1749.6 = 126w^2 + 680.4w \n" ); document.write( "--- \n" ); document.write( "126w^2 + 32.4w - 1749 = 0 \n" ); document.write( "w = -3.599 or w = 3.857 \n" ); document.write( "Positive solution: \n" ); document.write( "walking rate = 3.857 mph \n" ); document.write( "================================== \n" ); document.write( "Cheers, \n" ); document.write( "Stan H. \n" ); document.write( " |