Helping students gain understanding and self-confidence in algebra.
Ara Anderson wrote:Phyllis is navigating her boat upstream in the Orinoco River. She plans to do a roundtrip voyage, heading back to where she began after circling around a buoy upstream. The speed of the current is 3 miles per hour. If Phyllis’ boat can travel 16 miles per hour in still water, how long does it take her to make her trip if the buoy is 2 miles from her starting point?
If I use my common sense, I would say that it takes Phyllis 15 minutes, because any time added going upstream would be made up for going downstream, so I could just solve this problem using 10mph as my rate: