document.write( "Question 835124: A troop of scouts hike to the scout cabin at the rate of 2 miles per hour. They ride back to headquarters at 18 miles per hour. If the round trip takes 10 hours, how far is headquarters from the cabin?\r
\n" ); document.write( "\n" ); document.write( "This is the equation I found. However, I don't understand where the nine came from or why their dividing the distance.
\n" ); document.write( "(d/2) + (d/18) = 10
\n" ); document.write( "(9d/18) + (d/18) = 10
\n" ); document.write( "10d/18 = 10
\n" ); document.write( "d=18 miles \n" ); document.write( "
Algebra.Com's Answer #503368 by richwmiller(17219)\"\" \"About 
You can put this solution on YOUR website!
d/2=9d/18 because 1/2*d=9/18*d
\n" ); document.write( "r*t=d
\n" ); document.write( "t=d/r
\n" ); document.write( "t=d/2
\n" ); document.write( "t=d/18
\n" ); document.write( "total time is 10 so add the two time parts of the round trip to get the total time
\n" ); document.write( "so from the beginning\r
\n" ); document.write( "\n" ); document.write( "d/2+d/18=10
\n" ); document.write( "find common denominator which is 18
\n" ); document.write( "1/2*d=9/18*d
\n" ); document.write( "9/18*d+d/18=10\r
\n" ); document.write( "\n" ); document.write( "10/18*d=10
\n" ); document.write( "divide by 10
\n" ); document.write( "d/18=1
\n" ); document.write( "d=18\r
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