document.write( "Question 1095352: A plane can fly 300 miles in the same time as it takes a car to go 100 miles. If the car travels 100 mph slower than the plane, find the speed of the plane. \n" ); document.write( "

Algebra.Com's Answer #709881 by ikleyn(52864) $\"\"$ $\"About$

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document.write( "Let r be the speed of the plane, in mph.\r\n" );
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document.write( "Then the speed of the car is (r-100) mph.\r\n" );
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document.write( "You then have this \"time\" equation\r\n" );
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document.write( " =         (\"A plane can fly 300 miles in the same time as it takes a car to go 100 miles\").\r\n" );
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document.write( "To solve it, cross-multiply. You will get\r\n" );
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document.write( "300*(r-100) = 100*r  ====>  300r - 30000 = 100r  ====>  200r = 30000  ====>  r =  = 150.\r\n" );
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document.write( "Thus the plane speed is 150 miles per hour.\r\n" );
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document.write( "Then the car' speed is 150-100 = 50 mph.\r\n" );
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