Question 921908
A boat has 2 motors. If the large motor is running, the fuel lasts 2 hours.If the small motor is running, the fuel lasts 4 hours. How long will the fuel last if both motors are running.
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let x=amt of time fuel will last with both motors running
1/x=their fuel burn rate
1/2=fuel burn rate of large motor
1/4=fuel burn rate of small motor
..
1/2+1/3=1/x
3/4=1/x
x=4/3
How long will the fuel last if both motors are running? 4/3 hrs