document.write( "Question 692308: A motorboat leaves a harbor at an average speed of 9mph toward a small island. Two hours later a cabin cruiser leaves the same harbor and travels at an average speed of 18mph toward the same island. In how many hours after the cabin cruiser leaves the harbor will it be alongside the motorboat? the answer i got was 4 hours but i am not sure if the method i did to get the answer is correct. \n" ); document.write( "

Algebra.Com's Answer #426961 by vleith(2983) $\"\"$ $\"About$

You can put this solution on YOUR website!
Assuming the island is far enough away that the motorboat doesnt get there before the cruiser catches up, the formula is based on $\"distance+=+speed+%2A+time\"$
\n" ); document.write( "The distance will be the same when the cruiser catches up. Let t be the time for the motorboat. Then $\"t-2\"$ is the time for the cruiser.
\n" ); document.write( " $\"Distance+Moterboat+=+Distance+cruiser\"$
\n" ); document.write( " $\"speedMotorBoat+%2A+t+=+SpeedCruiser+%2A+%28t-2%29\"$
\n" ); document.write( " $\"9+%2A+t+=+18%28t-2%29\"$
\n" ); document.write( " $\"9t+=+18t+-+36\"$
\n" ); document.write( " $\"36+=+9t\"$
\n" ); document.write( " $\"4+=+t\"$
\n" ); document.write( "So you are already correct. Way to go! \n" ); document.write( "

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