document.write( "Question 644534: A cargo plane flew to the maintence facility and back. It took one hour less time to get there than it did to get back. The average speed on the trip there was 220 mph. The average speed on the way back was 200 mph. How many hours did the trip there take? \n" ); document.write( "

Algebra.Com's Answer #405131 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let $\"+t+\"$ = time to get there
\n" ); document.write( "given:
\n" ); document.write( " $\"+t+%2B+1+\"$ = time to get back
\n" ); document.write( "Equation going there:
\n" ); document.write( "(1) $\"+d+=+220t+\"$
\n" ); document.write( "Equation coming back:
\n" ); document.write( "(2) $\"+d+=+200%2A%28+t+%2B+1+%29+\"$
\n" ); document.write( "---------------------
\n" ); document.write( "Substitute (1) into (2)
\n" ); document.write( "(2) $\"+220t+=+200%2A%28+t+%2B+1+%29+\"$
\n" ); document.write( "(2) $\"+220t+=+200t+%2B+200+\"$
\n" ); document.write( "(2) $\"+20t+=+200+\"$
\n" ); document.write( "(2) $\"+t+=+10+\"$
\n" ); document.write( "The trip there took 10 hours
\n" ); document.write( "check:
\n" ); document.write( "(1) $\"+d+=+220%2A10+\"$
\n" ); document.write( "(1) $\"+d+=+2200+\"$
\n" ); document.write( "and
\n" ); document.write( "(2) $\"+d+=+200%2A%28+10+%2B+1+%29+\"$
\n" ); document.write( "(2) $\"+d+=+200%2A11+\"$
\n" ); document.write( "(2) $\"+d+=+2200+\"$
\n" ); document.write( "OK \n" ); document.write( "

\n" );