document.write( "Question 216374: A river has a current of 5 mph. It takes Al half an hour longer to paddle upstream 1.2 miles than to paddle downstream the same distance. What is Al's rate in still water?\r
\n" ); document.write( "\n" ); document.write( "I started out with:
\n" ); document.write( "r=rate
\n" ); document.write( "With current=r+5
\n" ); document.write( "against current=r-5\r
\n" ); document.write( "\n" ); document.write( "but this is as far as I could get \n" ); document.write( "

Algebra.Com's Answer #163384 by Alan3354(69443) $\"\"$ $\"About$

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A river has a current of 5 mph. It takes Al half an hour longer to paddle upstream 1.2 miles than to paddle downstream the same distance. What is Al's rate in still water?
\n" ); document.write( "---------
\n" ); document.write( "Your statements are correct. Use them in the equations.
\n" ); document.write( "d = rt (r = Als rate)
\n" ); document.write( "t = 1.2/(r+5)
\n" ); document.write( "t+1/2 = 1.2/(r-5)
\n" ); document.write( "(1.2/(r+5)) + 1/2 = 1.2/(r-5)
\n" ); document.write( "Multiply by 2(r+5)*(r-5)
\n" ); document.write( "2.4(r-5) + (r+5)(r-5) = 2.4(r+5)
\n" ); document.write( "2.4r-12 + r^2-25 = 2.4r + 12
\n" ); document.write( "r^2 - 49 = 0
\n" ); document.write( "r = 7 mph
\n" ); document.write( "------
\n" ); document.write( "1.2 miles at 2 mph = 0.6 hours
\n" ); document.write( "1.2 miles at 12 mph = 0.1 hours, 1/2 hour less \n" ); document.write( "

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