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The distance between two cities is 30 Km. A man goes at a speed of 30 Km per hour and returns at 20 Km per hour. What is his average speed?
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The distance between two cities is 30 Km. A man goes at a speed of 30 Km per hour and returns at 20 Km per hour. What is his average speed?
1). 25 Km/hr
2). 24 Km/hr
3). 10 Km/hr
4). 26 Km/hr
2 answers
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Solution:
Distance taken for arriving at the city = 30 km
Distance taken for returning to the city = 30 km
Therefore, Total Distance = 30 + 30 = 60 km
Time taken to arrive at the city
= Distance taken to arrive at the city / Speed
= 30 km / 30 km per hour
= 1 hour
Time taken to return to the city
= Distance taken to return to the city/ Speed
= 30 km / 20 km per hour
= 1.5 hour
Total time taken = 1 + 1.5 = 2.5 hour
Average Speed = Total Distance / Total time
Average Speed = 60 km / 2.5 hour
Average Speed = 24 km per hour
The correct option is 2). 24 km/ hr