document.write( "Question 282326: Each day, Amit runs nine miles and then walks one mile. He runs 10 mph faster than he walks. If his total time is 75 minutes, then what is Amit's running speed? \n" ); document.write( "

Algebra.Com's Answer #854187 by MathTherapy(10801) $\"\"$ $\"About$

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document.write( "Each day, Amit runs nine miles and then walks one mile. He runs 10 mph faster than he walks.\r\n" );
document.write( "If his total time is 75 minutes, then what is Amit's running speed?\r\n" );
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document.write( "Let Amit's running-speed be S\r\n" );
document.write( "Since his running-speed is 10 mph faster than his walking-speed, then Amit's walking-speed is \"S - 10\" mph\r\n" );
document.write( "With his running distance being 9 miles, Amit's time to run these 9 miles is  \r\n" );
document.write( "And, with his walking distance being 1 mile, Amit's time to cover this mile is \r\n" );
document.write( "It's stated that Amit's total time to run and walk \"....is 75 minutes,\" or . This gives us the following\r\n" );
document.write( "total TIME equation: , with S > 10                                    \r\n" );
document.write( "                        9(4)(S - 10) + 4S = 5S(S - 10) --- Multiplying by LCD, 4S(S - 10)\r\n" );
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document.write( "                            (S - 12)(S - 6) = 0\r\n" );
document.write( "                                          S - 12 = 0     or      S - 6 = 0 ----- Setting FACTORS equal to 0\r\n" );
document.write( "                                                  S = 12 mph   or    6 mph. However, 6 is NOT > 10 (see above constraint).      \r\n" );
document.write( "  So, Amit's running-speed is 12 mph

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