1). A man goes from Delhi to Dehradun. Half the distance he covers by bus at an average speed of 50 Km/hr and the other half by train at an average speed of 70 Km/hr the average speed for the whole journey was
View Answer Correct Answer: None of these v = \( \large\frac{2uv}{u + v}\) = \(\frac{2 \times 50 \times 70}{50 + 70} \) = \( \large 58 \frac{1}{3} \) Km/hr
 
2). A person shooting at a target from a distance of 450 metres finds that the sound of the bullet hitting the target comes 1 / 2 seconds after he fired. A person equidistant from the target and shooting point hears the bullet hit 3 seconds after he heard the gun. The speed of sound is
View Answer Correct Answer: 300 m/s Average speed = \( \Large \frac{Total \ distance }{Total \ time} \)
 
3). A monkey climbs a slippery pole 12 m high. It rises 1 meter in every one minute and slips 1 /2 meter in every next minute. Find how soon it will reach the top?
View Answer Correct Answer: 45 min On first minute monkey climbs 1 meter. On second minute it slips 1 / 2 meter. For every two minute it climbs 1 / 2 meter. So Average speed = 1 meter / 4 minutes For 11 meters, time taken = 44 minutes. For last 1 meter jump add 1 minute. So time taken = 45 minutes.
 
4). A boy walks at 4 Km/hr and reaches his school 5 minutes late. Next day he walks at 5 Km/hr and start at the same time, reaches his school 10 minutes early. How far the school is from his house
View Answer Correct Answer: 5 kms \( \Large \frac{d}{4}  \frac{d}{5} \) = \( \Large \frac{15}{60} \)
 
5). A train starts from Delhi with a certain number of passengers. At Ghaziabad 110 get down and 100 get in. At Aligarh 50% get down and 25 get in. At Kanpur 5 of them get down and 50 get in. When train leaves Kanpur there are 200 passengers. How many did board the train at Delhi?
View Answer Correct Answer: 270 Let the total number of passenger be 'x' that had boarded at Delhi.
 
6). The radius of a circular wheel is 35 cm and it moves at the rate of 500 revolutions per minute. The speed of wheel is.
View Answer Correct Answer: 66 Km/hr r = 35 cm = \( \Large \frac{35}{100000}km \)
 
7). A person has to make a journey of 72 Kms. He rides a cycle at 12 Km/hr. After going certain distance, the cycle got punctured and he walks the remaining distance at \( \Large 4\frac{1}{2} \)Km/hr. Where did the cycle got punctured if the total time taken for the journey was \(8 \frac{1}{2} \) hours?
View Answer Correct Answer: 54 Kms \( \Large 8\frac{1}{2}\) = \( \Large \frac{x}{12} + \frac{72  x}{4\frac{1}{2}}\)
 
8). A train travelled from A to B and back in a certain time at the rate of 60 Km/hr. But if the train had travelled from A to B at the rate of 80 Km/hr and back from B to A at the rate of 40 Km/hr it would take two hours longer. The distance between A and B is
View Answer Correct Answer: 480 km \( \Large \left(\frac{d}{80}+ \frac{d}{40} \right)  \left(\frac{d}{60}+ \frac{d}{60} \right) = 2 \)
 
9). P and Q are two stations 50 Km apart. X left stations P for station Q at the speed of 4 Km/hr and Y left station Q for station P at the speed of 6 Km/hr. They cross each other after
View Answer Correct Answer: 5 hrs t = \( \Large \frac{50}{4 + 6} = 5 hrs\)
 
10). Walking at 4 Km/hr a man reaches his office 5 minutes late. If he walks at 5 Km/hr he will be \(\Large 2\frac{1}{2} \) minutes early. The distance of his office from his house is
View Answer Correct Answer: 2.5 km \( \Large \frac{d}{4}  \frac{d}{5} = \frac{7\frac{1}{2}}{60} \)

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