document.write( "Question 218393: the question reads: In a bicycle race, Lionel gives Robert a 500 meter advantage. Lionel also agrees to start 15 minutes after Robert. If Lionel bikes at 17 km/h and Robert at 14 km/h how long will it take Lionel after he starts biking to overtake Robert?\r
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document.write( "so I set up a chart:\r
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document.write( " Time x Rate = Distance
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document.write( "Lionel t+1/4 17 d + 1/2 (km)
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document.write( "Robert t 14 d\r
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document.write( "then I have the equations:\r
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document.write( "17(t+1/4) = d + 1/2 and 14t=d\r
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document.write( "so I solve:\r
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document.write( "17t + 17/4 = 14t + 1/2
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document.write( "3t = -15/4
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document.write( "and i get t = to a negative number\r
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document.write( "how is that possible?
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Algebra.Com's Answer #164659 by ankor@dixie-net.com(22740)![]() ![]() You can put this solution on YOUR website! In a bicycle race, Lionel gives Robert a 500 meter advantage. Lionel also agrees to start 15 minutes after Robert. If Lionel bikes at 17 km/h and Robert at 14 km/h how long will it take Lionel after he starts biking to overtake Robert? \n" ); document.write( ": \n" ); document.write( "Let's do it this way and then compare what you did \n" ); document.write( ": \n" ); document.write( "Let t = L's travel time \n" ); document.write( "then \n" ); document.write( "(t+.25) = R's travel time \n" ); document.write( ": \n" ); document.write( "A distance equation: \n" ); document.write( "L's dist - .5 km = R's dist \n" ); document.write( "17t - .5 = 14(t+.25) \n" ); document.write( "17t - .5 = 14t + 3.5 \n" ); document.write( "17t - 14t = 3.5 + .5 \n" ); document.write( "3t = 4 \n" ); document.write( "t = \n" ); document.write( ": \n" ); document.write( ": \n" ); document.write( "Check solution by finding the distance each traveled using decimals \n" ); document.write( "17 * 1.33 = 22.6 km \n" ); document.write( "14 * (1.33 +.25) = 22.1 mi \n" ); document.write( "a difference of .5 km \n" ); document.write( ": \n" ); document.write( ": \n" ); document.write( "I think you had L starting before R instead of the other way around. \n" ); document.write( " \n" ); document.write( " |