Two cars X and Y start at the same point and travel towards a point P which is 150km away. If the average speed of Y is 60km per hour and x arrives at P 25 minutes earlier than Y. What is the average speed of X?
A. 51\(\frac{3}{7}\)km per hour B. 72km per hour C. 37\(\frac{1}{2}\) km per hour D. 66km per hour E. 75km per hour
Correct Answer: B
Explanation
Distance travelled by both x and y = 150 km. Speed of y = 60km per hour, Time = \(\frac{dist.}{Speed}\) Time spent by y = \(\frac{150}{60}\) = 2\(\frac{3}{6}\)hrs = \(\frac{1}{2}\) hrs if x arrived at p 25 minutes earlier than y, then time spent by x = 2 hour 5 mins = 125 mins x average speed = \(\frac{150}{125}\) x \(\frac{60}{1}\) = \(\frac{9000}{125}\) = 72 km\hr
