document.write( "Question 206567: Craig Drives 20 miles per hour faster than sara. in the same time that sara drives 225 miles, craig drives 325 miles. find the speed of each car \n" ); document.write( "

Algebra.Com's Answer #854665 by ikleyn(53937) $\"\"$ $\"About$

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\n" ); document.write( "Craig Drives 20 miles per hour faster than sara.
\n" ); document.write( "in the same time that sara drives 225 miles, craig drives 325 miles. find the speed of each car
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\n" ); document.write( "\n" ); document.write( "        The answer in the post by @HyperBrain is INCORRECT due to arithmetic error on the way.\r
\n" ); document.write( "\n" ); document.write( "        I came to provide a correct solution\r
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\n" ); document.write( "\n" ); document.write( "d=vt so t=d/v
\n" ); document.write( "Let x be the Sara's speed, in miles per hour.
\n" ); document.write( "Then the Craig's speed is (x+20) miles per hour.
\n" ); document.write( "225/x=325/(x+20)
\n" ); document.write( "Multiply both sides by x(x+20)
\n" ); document.write( "225(x+20)=325x
\n" ); document.write( "225x+4500=325x
\n" ); document.write( "100x=4500
\n" ); document.write( "x = 45 mi/hr ((Sara' speed)
\n" ); document.write( "x+20 = 45 + 20 = 65 mi/hr (Craig' speed).\r
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\n" ); document.write( "\n" ); document.write( "CHECK the travel time.    $\"225%2F45\"$ = 5 hours.    $\"325%2F65\"$ = 5 hours.     Precisely correct !\r
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\n" ); document.write( "\n" ); document.write( "Solved correctly.\r
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