A car drives 40 miles on local roads at 20 mph, and 180 miles on the h

Question

A car drives 40 miles on local roads at 20 mph, and 180 miles on the highway at 60 mph, what is the average speed of the entire trip?

A. 36 mph
B. 40 mph
C. 44 mph
D. 52 mph
E. 58 mph

sterling19 · Answer

40 miles at 20 mph takes 2 hours
180 miles at 60 mph takes 3 hours

Average speed = Total distance / Total time 
= (40 + 180) / (2 + 3) 
= 220 / 5
= 44

The correct answer is C.

mehrdadtaheri92 · Answer

So The Answer is Plainly C....

we have a general relation for speed , time and distance : v (velocity) * t ( time)= d (distance)

for first part we have d=40 miles , and v= 20 mph so we can obtain time : 20*t = 40 Or t= 40/20 = 2 hours the needed time to cover 40 miles

in the same way we should divide 180 to 60 to find the needed time to cover 180 miles ,so t= 3 hours

so the total time for covering total distance would be 3+2 = 5 hours and total distance is 40+180= 220 miles

Final stage : average speed is total distance divide to total time : 220/5 = 44 miles per hour....

PareshGmat · Answer

Answer = C. 44 mph

Average speed  = \frac{Total distance}{Total time} = \frac{40+180}{\frac{40}{20} + \frac{180}{60}} = \frac{220}{5} = 44

Bunuel · Answer

MAGOOSH OFFICIAL SOLUTION:

In phase #1 of the trip, the car traveled 40 mi at 20 mph. That time of this phase was:
time = distance/rate = (40 mi)/(20 mph) = 2 hr
 
In phase #2 of the trip, the car traveled 180 mi at 60 mph. That time of this phase was:
time = distance/rate = (180 mi)/(60 mph) = 3 hr
 
The total distance of the trip = 40 mi + 180 mi = 220 mi
The total time of the trip = 2 hr + 3 hr = 5 hr
The average speed of trip is given by
speed = distance/time = (220 mi)/(5 hr) = 44 mph

Answer: C.

ronny123 · Answer

Average Speed = (Total Distance traveled) / (Total Time taken)

Total Distance = 40 +180 = 220 miles
Total Time = (40/20) +(180/60) = 2 + 3 = 5 hours

Average Speed = 220 /5 = 44 mph
Correct Option : C

Chethan92 · Answer

Average time = Total distance/Total time taken.

Average time = 220/5 = 44

C is the answer

Posted from my mobile device

Abhishek009 · Answer

Time taken for first  40  miles is \frac{40}{20} =  2  Hours
Time taken for next  180  miles is \frac{180}{50} =  3  Hours

So, For travelling 220 miles time taken is 5 Hours.

So, Avg Speed is  \frac{220}{5} = 44 \ mph , Answer must be (C)

bumpbot · Answer

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A car drives 40 miles on local roads at 20 mph, and 180 miles on the h

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A car drives 40 miles on local roads at 20 mph, and 180 miles on the h

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