document.write( "Question 1057326: Carol requires 3 hours to go downstream 21 miles in her motorized boat. Her return trip upstream requires 3 1/2 hours. Assuming that Carol's boat motor runs at a constant pace, find the speed of her boat in still water. \n" ); document.write( "

Algebra.Com's Answer #672378 by MathTherapy(10555) $\"\"$ $\"About$

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Carol requires 3 hours to go downstream 21 miles in her motorized boat. Her return trip upstream requires 3 1/2 hours. Assuming that Carol's boat motor runs at a constant pace, find the speed of her boat in still water.
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With speed in still water being S, we get the following system of TOTAL AVERAGE-SPEED equations: 
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document.write( "_______S + C = 7 ------- eq (i)
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document.write( "____S - C = 6 ------- eq (ii)
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document.write( "Add eqs (ii) & (i) to get value of S. You should get: 
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document.write( "That's it...nothing COMPLEX!! \n" );
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