Average speed
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Martha takes a road trip from point A to point B. She drives x percent of the distance at 60 miles per hour and the remainder at 50 miles per hour. If Martha's average speed for the entire trip is represented as a fraction in its reduced form, in terms of x, which of the following is the numerator?
(A) 110
(B) 300
(C) 1,100
(D) 3,000
(E) 30,000
Average Speed from ManhattanGmat
This topic has expert replies
I think answer is E. here is My explanantion.
Total distance = y
Total time = (XY/100)/60 + (100-x)y/50*100
Average Speed = Total distance /Total time
= 1/(x/6000 + 100-x/5000)
=30000/(5x + 600 - 6x)
= 30000/(600-x)
hence answer is E.Please Correct me if I am wrong
Total distance = y
Total time = (XY/100)/60 + (100-x)y/50*100
Average Speed = Total distance /Total time
= 1/(x/6000 + 100-x/5000)
=30000/(5x + 600 - 6x)
= 30000/(600-x)
hence answer is E.Please Correct me if I am wrong
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