Speed

[Marisa]

A car average 25 miles/gallon when driven in a city and 40 mi/g when driven on a highway. If the car drives 10 miles in the city and 50 miles on the highway, what is the average miles/gallon?

I believe this is similar to the production line questions; however, I did not get the correct answer.

[Mr2Bits]

I get about 37MPG the car averaged.

60/65 = miles traveled over total MPG = 12/13 * 40MPG as most was driven - about 37.5

Or by the numbers above you know that 5/6 of the distance was driven at 40mpg and 1/6 at 10 mpg add up and divide by total (40+40+40+40+40+25) = 225/6 = 37.5

Whats the answer?

[Marisa]

Thank you. The OA is 36.

[Mr2Bits]

Thank you. The OA is 36.

Was 37 a possibility? If so, Ive messed up somewhere

[lilu]

Please refer to this thread:
https://www.beatthegmat.com/average-t9149.html

[scoobydooby]

mr2bits,
we cant add up the miles/gallons in the denominator.
we want the total miles/total gallons.

total distance: 60

gallons for city travel:
25m-1g, so for 10m it consumes 10/25=2/5g

gallons for highway travel:
40m-1g, so for 50m it consumes 50/40=5/4g

Average Miles/g=60/(2/5+5/4)=60*20/33=400/11=36.37~
guess it must have been rounded to 36