document.write( "Question 849732: A certain trip takes 40 minutes. If half the distance is travelled at an avg speed of 100km/h and the other half at an avg speed of 60km/h, what was the distance travelled during the trip. \n" ); document.write( "

Algebra.Com's Answer #511713 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let $\"+t+\"$ = time for the 1st half of the trip
\n" ); document.write( " $\"+40%2F60+-+t+\"$ = time for the 2nd half of the trip
\n" ); document.write( "(1) $\"+d%2F2+=+100t+\"$
\n" ); document.write( "(2) $\"+d%2F2+=+60%2A%28+40%2F60+-+t+%29+\"$
\n" ); document.write( "----------------------------
\n" ); document.write( "(1) $\"+d+=+200t+\"$
\n" ); document.write( "(2) $\"+d%2F2+=+40+-+60t+\"$
\n" ); document.write( "(2) $\"+d+=+80+-+120t+\"$
\n" ); document.write( "----------------------
\n" ); document.write( "Substitute (1) into (2)
\n" ); document.write( "(2) $\"+200t+=+80+-+120t+\"$
\n" ); document.write( "(2) $\"+320t+=+80+\"$
\n" ); document.write( "(2) $\"+t+=+1%2F4+\"$
\n" ); document.write( "and
\n" ); document.write( "(1) $\"+d+=+200t+\"$
\n" ); document.write( "(1) $\"+d+=+200%2A%281%2F4%29+\"$
\n" ); document.write( "(1) $\"+d+=+50+\"$
\n" ); document.write( "The distance traveled is 50 km
\n" ); document.write( "check:
\n" ); document.write( "(2) $\"+50%2F2+=+60%2A%28+40%2F60+-+1%2F4+%29+\"$
\n" ); document.write( "(2) $\"+25+=+40+-+15+\"$
\n" ); document.write( "(2) $\"+25+=+25+\"$
\n" ); document.write( "OK\r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

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