Question 186865
One day Eli set out for a trip across the lake on his motorboat at a rate
 of 8 mph. Along the way the motor broke down. Eli rowed back at a rate of
 2 mph. He was gone for 5 hrs. How far did Eli row?
:
Let d = distance he rowed (and distance he went before he broke down)
:
Write a time equation: Time = {{{dist/speed}}}
:
Time motoring + time rowing = 5 hrs
{{{d/8}}} + {{{d/2}}} = 5
Multiply equation by 8:
d + 4d = 8(5)
5d = 40
d = {{{40/5}}}
d = 8 mi, he rowed his boat
:
:
Check solution by finding the times:
8/8 = 1hr
8/2 = 4hr
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total 5 hr