document.write( "Question 756904: Some bank robbers leave town, speeding at 100 mph. 15 minutes later, the police give chase, traveling at 110 mph. How long (in hours) will it take the police to overtake the robbers? \n" ); document.write( "

Algebra.Com's Answer #460523 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Convert $\"+15+\"$ min to $\"+.25+\"$ hrs
\n" ); document.write( "The robbers have a head start of
\n" ); document.write( " $\"+d%5B1%5D+=+100%2A%28.25+%29+\"$
\n" ); document.write( " $\"+d%5B1%5D+=+25+\"$ mi
\n" ); document.write( "----------------
\n" ); document.write( "Start a stopwatch when the police leave.
\n" ); document.write( "Let $\"+t+\"$ = time on stopwatch when police catch robbers
\n" ); document.write( "Let $\"+d+\"$ = the distance the police travel until they catch robbers
\n" ); document.write( "----------------
\n" ); document.write( "Robbers equation:
\n" ); document.write( " $\"++d+-+25+=+100t+\"$
\n" ); document.write( "Police equation:
\n" ); document.write( " $\"+d+=+110t+\"$
\n" ); document.write( "------------
\n" ); document.write( "By substitution:
\n" ); document.write( " $\"+110t+-+25+=+100t+\"$
\n" ); document.write( " $\"+10t+=+25+\"$
\n" ); document.write( " $\"+t+=+2.5+\"$
\n" ); document.write( "-----------
\n" ); document.write( "It takes the police 2 hrs and 30 min to catch robbers
\n" ); document.write( "check:
\n" ); document.write( " $\"+d+=+110t+\"$
\n" ); document.write( " $\"+d+=+110%2A2.5+\"$
\n" ); document.write( " $\"+d+=+275+\"$
\n" ); document.write( "and
\n" ); document.write( " $\"++d+-+25+=+100%2A2.5+\"$
\n" ); document.write( " $\"+d+=+25+%2B+250+\"$
\n" ); document.write( " $\"+d+=+275+\"$
\n" ); document.write( "OK
\n" ); document.write( " \n" ); document.write( "

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