Problem Solving (PS) | Re: A company’s four cars running 10 hrs a day consume 1200 lts of fuel in

my solution
X - fuel consumption rate
4*x*10*10 = 1200 solve for x = 3 per mile
In next 6 days for those 4 cars
4*3*6*12=12*72=864
So for the new 5 cars fuel consumption rate is 20% of 3, which makes 12/5
Then 5*12/5*6*12=12*72=864
Total 864 + 864 = 1728

Actually when you get total fuel consumption for the first group of cars there is no need to calculate for the other one, as fuel consumption rate decreases for 20% but the number of car increases by the same 20% from 4 to 5. Just double 864

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