document.write( "Question 1192951: A kayak can travel 48 miles downstream in 4 hours, while it would take 24 hours to make the same trip upstream. Find the speed of the kayak in still water, as well as the speed of the current. Let k represent the speed of the kayak in still water, and let c represent the speed of the current. \n" ); document.write( "
Algebra.Com's Answer #824895 by ankor@dixie-net.com(22740)![]() ![]() You can put this solution on YOUR website! A kayak can travel 48 miles downstream in 4 hours, while it would take 24 hours to make the same trip upstream. \n" ); document.write( " Find the speed of the kayak in still water, as well as the speed of the current. \n" ); document.write( " Let k represent the speed of the kayak in still water, and let c represent the speed of the current. \r \n" ); document.write( "\n" ); document.write( "Write a distance equation for each way, dist = time * speed \n" ); document.write( "4k + 4c = 48 \n" ); document.write( "and \n" ); document.write( "24k - 24c = 48 \n" ); document.write( "simplify, divide by6 \n" ); document.write( "4k - 4k = 8 \n" ); document.write( ": \n" ); document.write( "Add these two equation \n" ); document.write( "4k + 4c = 48 \n" ); document.write( "4k - 4c = 8 \n" ); document.write( "----------------addition eliminates c, find k \n" ); document.write( "8k + 0 = 56 \n" ); document.write( "k = 56/8 \n" ); document.write( "k = 7 mph is speed of the kayak in still water \n" ); document.write( "then using the first equation and k=7 \n" ); document.write( "4(7) + 4c = 48 \n" ); document.write( "28 + 4c = 48 \n" ); document.write( "4c = 48 - 28 \n" ); document.write( "4c = 20 \n" ); document.write( "c = 20/4 \n" ); document.write( "c = 5 mph is the rate of the current \n" ); document.write( ": \n" ); document.write( ": \n" ); document.write( "Check this in the original 2nd equation \n" ); document.write( "24(7) - 24(5) = \n" ); document.write( "168 - 120 = 48 \n" ); document.write( " \n" ); document.write( " |