document.write( "Question 896685: A boat travels for 3 hours with the current at speed of 10kph and returns the same distance against the current an hour more. Determine the boat's speed in still water. \n" ); document.write( "
Algebra.Com's Answer #543708 by thesvw(77)\"\" \"About 
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Lets find the distance.\r
\n" ); document.write( "\n" ); document.write( "\"3%2A10+=+30\" km\r
\n" ); document.write( "\n" ); document.write( "Velocity of the boat against current = 30/4 kph\r
\n" ); document.write( "\n" ); document.write( "Boat velocity with current = Boat velocity (V) + current velocity (C)\r
\n" ); document.write( "\n" ); document.write( "\"10+=+V+%2B+C\"\r
\n" ); document.write( "\n" ); document.write( "And against current ..\r
\n" ); document.write( "\n" ); document.write( "\"30%2F4+=+V+-+C\"\r
\n" ); document.write( "\n" ); document.write( "Add both equations\r
\n" ); document.write( "\n" ); document.write( "\"10+%2B30%2F4+=+2V\"\r
\n" ); document.write( "\n" ); document.write( "\"70%2F4+=+2V\"\r
\n" ); document.write( "\n" ); document.write( "\"V+=+70%2F8+=+8.75\" kph
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