document.write( "Question 867370: A train traveling 100 miles at m miles per hour arrived at its destination 1 hour late.How many miles an hour should it have traveled to arrive on time ? \n" ); document.write( "

Algebra.Com's Answer #522985 by josmiceli(19441) $\"\"$ $\"About$

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Let $\"+t+\"$ = the time in hours to arrive on time
\n" ); document.write( " $\"+d+=+r%2At+\"$
\n" ); document.write( " $\"+100+=+m%2A%28+t+%2B+1+%29+\"$
\n" ); document.write( " $\"+100+=+m%2At+%2B+m+\"$
\n" ); document.write( " $\"+m%2At+=+100+-+m+\"$
\n" ); document.write( " $\"+t+=+%28+100+-+m+%29+%2F+m+\"$
\n" ); document.write( "------------------------------
\n" ); document.write( " $\"+100+=+r%2A%28+100+-+m+%29+%2F+m+\"$
\n" ); document.write( " $\"+r+=+100m+%2F+%28+100+-+m+%29+\"$
\n" ); document.write( "is the rate to arrive on time
\n" ); document.write( "-----------------------------------
\n" ); document.write( "check:
\n" ); document.write( "Suppose $\"+m+=+75+\"$
\n" ); document.write( " $\"+100+=+m%2A%28+t+%2B+1+%29+\"$
\n" ); document.write( " $\"+100+=+75%2A%28+t+%2B+1+%29+\"$
\n" ); document.write( " $\"+t+%2B+1+=+4%2F3+\"$
\n" ); document.write( " $\"+t+=+1%2F3+\"$
\n" ); document.write( "----------------------
\n" ); document.write( " $\"+r+=+100m+%2F+%28+100+-+m+%29+\"$
\n" ); document.write( " $\"+r+=+100%2A75+%2F+%28+100+-+75+%29+\"$
\n" ); document.write( " $\"+r+=+7500+%2F+25+\"$
\n" ); document.write( " $\"+r+=+300+\"$
\n" ); document.write( "---------------------
\n" ); document.write( " $\"+d+=+r%2At+\"$
\n" ); document.write( " $\"+100+=+300%2At+\"$
\n" ); document.write( " $\"+t+=+1%2F3+\"$
\n" ); document.write( "OK\r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

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