document.write( "Question 619229: Andy travels 315 km, half as much time by car 60km/h as by train at 75km/h. How long did he travel by each mode? \n" ); document.write( "

Algebra.Com's Answer #389506 by ankor@dixie-net.com(22740) $\"\"$ $\"About$

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Andy travels 315 km, half as much time by car 60km/h as by train at 75km/h.
\n" ); document.write( " How long did he travel by each mode?
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\n" ); document.write( "Let t = travel time by car
\n" ); document.write( "then twice as much time by train
\n" ); document.write( "2t = travel time by train
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\n" ); document.write( "Write a distance equation; dist = speed * time
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\n" ); document.write( "Car dist + train dist = 315 km
\n" ); document.write( "60t + 75(2t) = 315
\n" ); document.write( "60t + 150t = 315
\n" ); document.write( "210t = 315
\n" ); document.write( "t = 315/210
\n" ); document.write( "t = 1.5 hrs by car
\n" ); document.write( "then
\n" ); document.write( "2(1.5) = 3 hrs by train
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\n" ); document.write( "Check: 1.5(60) + 3(75) = 315, confirms our solution \n" ); document.write( "

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