document.write( "Question 981685: Please help me with this problem.
\n" ); document.write( "Write an equation that can be used to solve the problem. Solve the equation and answer the question. A sigh- seeing boat travels at an average speed of 20 miles per hour in the calm water of a large lake. The same boat is used for sigh- seeing in a nearby river. In the river the boat travels 2.9 miles downstream (with the current) in the same amount of time it takes to travel 2.5 miles upstream (against the current)
\n" ); document.write( "Find the current of the river.
\n" ); document.write( "This is a very large problem and I would be extremely grateful if you could help me. \n" ); document.write( "

Algebra.Com's Answer #602682 by MathTherapy(10551) $\"\"$ $\"About$

You can put this solution on YOUR website!

\n" ); document.write( "Please help me with this problem.
\n" ); document.write( "Write an equation that can be used to solve the problem. Solve the equation and answer the question. A sigh- seeing boat travels at an average speed of 20 miles per hour in the calm water of a large lake. The same boat is used for sigh- seeing in a nearby river. In the river the boat travels 2.9 miles downstream (with the current) in the same amount of time it takes to travel 2.5 miles upstream (against the current)
\n" ); document.write( "Find the current of the river.
\n" ); document.write( "This is a very large problem and I would be extremely grateful if you could help me.
\n" ); document.write( "

It's not as \"large\" or as difficult as you may think!\r
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document.write( "Let speed of current be C
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document.write( "Total speed when going DOWNSTREAM: 20 + C (boat's speed, plus current's speed)
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document.write( "Total speed when going UPSTREAM:   20 - C (boat's speed, less current's speed)
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document.write( "Time taken to travel 2.9 miles downstream: 
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document.write( "Time taken to travel 2.5 miles upstream: 
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document.write( "Since travel times are equal, we get: 
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document.write( "2.9(20 - C) = 2.5(20 + C) ---------- Cross-multiplying
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document.write( "58 - 2.9C = 50 + 2.5C 
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document.write( "- 2.9C - 2.5C = 50 - 58 
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document.write( "- 5.4C = - 8
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document.write( "C, or speed of current = , or  mph \n" );
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