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Ying Zyiyu covered the first 300 miles of a trip going at 60 mph and the last hundred going at 40 mph. What was his average speed for the entire trip?

User Atomix
by
5.2k points

2 Answers

3 votes

Answer:

53.33 mph

Explanation:

I just wanted to say that the other guy's answer is correct, I checked :)

User Surenyonjan
by
5.6k points
7 votes

Answer:

53.33mph

Explanation:

Let's calculated the total time spent on the journey first;

For the first 300miles the time spent is ;

From Distance = speed× time

time = Distance/ speed

= 300/60 = 5 hours

Similarly for the last 100mile the time taken is ;

100/40 = 2.5 hours

Total time spent = 5 +2.5 = 7.5 hours

Total distance covered 400miles

Therefore average speed = 400/7.5 =53.33mph

User Prola
by
5.7k points