document.write( "Question 181807: A sightseeing boat travels 3 hrs. on a trip downstream with a 2.5mph current. The return trip against the same current takes 3.5 hrs. Find the speed of the boat in still water. \n" ); document.write( "
Algebra.Com's Answer #136419 by ankor@dixie-net.com(22740)\"\" \"About 
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A sightseeing boat travels 3 hrs. on a trip downstream with a 2.5mph current.
\n" ); document.write( " The return trip against the same current takes 3.5 hrs.
\n" ); document.write( " Find the speed of the boat in still water.
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\n" ); document.write( "Let s = boat speed in still water
\n" ); document.write( "then
\n" ); document.write( "(s+2.5) = speed down-stream
\n" ); document.write( "and
\n" ); document.write( "(s-2.5) = speed up-stream
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\n" ); document.write( "Distance of each trip is the same. Write a dist equation: dist = time * speed
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\n" ); document.write( "Dist up = dist down
\n" ); document.write( "3.5(s-2.5) = 3(s+2.5)
\n" ); document.write( ":
\n" ); document.write( "3.5s - 8.75 = 3s + 7.5
\n" ); document.write( ":
\n" ); document.write( "3.5s - 3s = 7.5 + 8.75
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\n" ); document.write( ".5s = 16.25
\n" ); document.write( "s = \"16.25%2F.5\"
\n" ); document.write( "s = 32.5 mph in still water
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\n" ); document.write( "Check solution by finding the distance of each:
\n" ); document.write( "3.5 * 30 = 105 mi
\n" ); document.write( "3.0 * 35 = 105 mi \n" ); document.write( "
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