document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1200510>Question 1200510</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A motorboat can maintain a constant speed of 34 miles per hour relative to the water.  The boat makes a trip upstream to a certain point in 35 ​minutes; the return trip takes 33  minutes.  What is the speed of the​ current? </SPAN>\n" );
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document.write( "The two responses you have received until now both show a rather standard formal algebraic method for solving the problem.<br><BR>\n" );
document.write( "Here is an alternative method that can be useful if the given information is in this particular form.<br><BR>\n" );
document.write( "The distances are the same, and the ratio of the upstream and downstream times is 35:33, so the ratio of the upstream and downstream speeds is 33:35.<br><BR>\n" );
document.write( "If the speed of the current is c, then the upstream and downstream speeds are 34-c and 34+c, so we have the proportion<br><BR>\n" );
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document.write( "That can be solved by inspection -- the speed of the current is c = 1.<br><BR>\n" );
document.write( "ANSWER: The speed of the current is 1 mph<br><BR>\n" );
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