document.write( "Question 1053938: Debra's boat has a top speed of 6 miles per hour in still water. While traveling on a river at top speed, she went 10 miles upstream in the same amount of time she went 30 miles downstream. Find the rate of the river current. \n" ); document.write( "

Algebra.Com's Answer #669120 by ikleyn(52790) $\"\"$ $\"About$

You can put this solution on YOUR website!
.
\n" ); document.write( "Debra's boat has a top speed of 6 miles per hour in still water. While traveling on a river at top speed,
\n" ); document.write( "she went 10 miles upstream in the same amount of time she went 30 miles downstream. Find the rate of the river current.
\n" ); document.write( "~~~~~~~~~~~~~~~~~~~~~~~\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "

\r\n" );
document.write( "Your governing equation is \"time\" equation\r\n" );
document.write( "\r\n" );
document.write( " = .\r\n" );
document.write( "\r\n" );
document.write( "Here the left side is the time for travel 10 miles upstream at the speed (6-v) mph, where v is the current speed.\r\n" );
document.write( "\r\n" );
document.write( "The right side is the time for travel 30 miles downstream at the speed (6+v) mph.\r\n" );
document.write( "\r\n" );
document.write( "To solve the equation, multiply both sides by (6-v)*(6+v). You will get\r\n" );
document.write( "\r\n" );
document.write( "10*(6+v) = 30*(6-v),  or\r\n" );
document.write( "\r\n" );
document.write( "60 + 10v = 180 -30v,  or\r\n" );
document.write( "\r\n" );
document.write( "40v = 120  --->  v =  = 3.\r\n" );
document.write( "\r\n" );
document.write( "Answer.  The rate of the river current is 3 mph.\r\n" );
document.write( "

\r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

\n" );