document.write( "Question 721115: A plane can fly 600 miles in the same time it takes a car to go 240 miles. If the car travels 90 mph slower than the plane, find the speed of the plane \n" ); document.write( "

Algebra.Com's Answer #442201 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let $\"+t+\"$ = the time for both
\n" ); document.write( "Let $\"+p+\"$ = the speed of the plane
\n" ); document.write( " $\"+p+-+90+\"$ = the speed of the car
\n" ); document.write( "Equation for car:
\n" ); document.write( "(1) $\"+240+=+%28+p-90+%29%2At+\"$
\n" ); document.write( "Equation for plane:
\n" ); document.write( "(2) $\"+600+=+p%2At+\"$
\n" ); document.write( "----------------
\n" ); document.write( "(2) $\"+t+=+600%2Fp+\"$
\n" ); document.write( "and
\n" ); document.write( "(1) $\"+240+=+%28+p+-+90+%29%2A%28+600%2Fp%29+\"$
\n" ); document.write( "(1) $\"+240+=+600+-+54000%2Fp+\"$
\n" ); document.write( "(1) $\"+240p+=+600p+-+54000+\"$
\n" ); document.write( "(1) $\"+360p+=+54000+\"$
\n" ); document.write( "(1) $\"+p+=+150+\"$
\n" ); document.write( "The plane's speed is 150 mi/hr
\n" ); document.write( "check:
\n" ); document.write( "(2) $\"+600+=+p%2At+\"$
\n" ); document.write( "(2) $\"+t+=+600%2F150+\"$
\n" ); document.write( "(2) $\"+t+=+4+\"$ hrs
\n" ); document.write( "and
\n" ); document.write( "(1) $\"+240+=+%28+p-90+%29%2At+\"$
\n" ); document.write( "(1) $\"+240+=+%28+150-90+%29%2At+\"$
\n" ); document.write( "(1) $\"+240+=+60t+\"$
\n" ); document.write( "(1) $\"+t+=+4+\"$ hrs
\n" ); document.write( "OK
\n" ); document.write( " \n" ); document.write( "

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