Quiz Discussion

If A travels to his school from his house at the speed of 3 km/h, then he reaches the school 5 minutes late. If he travels at the speed of 4 km/h, he reaches the school 5 minutes earlier than school time. The distance of his school from his house is:

• 1] 1 km
• 2] 2 km
• 3] 3 km
• 4] 4 km

A train covers a distance of 10 km in 12 minutes. If its speed is decreased by 5 km/hr, the time taken by it to cover the same distance will be :

• 1] 10 minutes
• 2] 13 minutes 20 seconds
• 3] 13 minutes
• 4] 11 minutes 20 seconds

A and B start from the same point and in the same direction at 7 am to walk around a rectangular field 400 m × 300 m. A and B walk at the rate of 3 km/hr and 2.5 km/hr respectively. How many times shall they cross each other if they continue to walk till 12.30 pm ?

• 1] Not even once
• 2] Once
• 3] Twice
• 4] Thrice

A boat covers 48 km upstream and 72 km downstream in 12 hours, while it covers 72 km upstream and 48 km downstream in 13 hours The speed of stream is :

• 1] 2 kmph
• 2] 2.2 kmph
• 3] 2.5 kmph
• 4] 4 kmph

Two runner start running together for a certain distance, one at 5 km/h and another at 8 km/h. The former arrives one and half an hour before the latter. The distance in Km is :

• 1] 12 km
• 2] 20 km
• 3] 25 km
• 4] 36 km

The diameter of each wheel of car is 70 cm. If each wheel rotates 400 times per minutes, then the speed of the car (in km/hr) if : \(\left( {{ \text{Take }}pi = \frac{{22}}{7}} \right)\)

• 1] 5.28 km/hr
• 2] 528 km/hr
• 3] 52.8 km/hr
• 4] 0.528 km/hr

Two cyclists start on a circular track from a given point but in opposite directions with speeds of 7 m/sec and 8 m/sec respectively. If the circumference of the circle is 300 metres, after what time will they meet at the starting point ?

• 1] 20 sec
• 2] 100 sec
• 3] 200 sec
• 4] 300 sec

Walking \(\frac{3}{4}\) of his normal speed, Rabi is 16 minutes late in reaching his office. The usual time is taken by him to cover the distance between his home and office:

• 1] 48 min.
• 2] 60 min.
• 3] 42 min.
• 4] 62 min.
• 5] 66 min.

The speed of a bus is 72 km /hr. The distance covered by the bus in 5 seconds is :

• 1] 100 metres
• 2] 60 metres
• 3] 50 metres
• 4] 74.5 metres

A hunter fired two shots from the branch of a tree at an interval of 76 seconds. A tiger separating too fast hears the two shots at an interval of 83 seconds. If the velocity of the sound is 1195.2 km/h, then find the speed of the tiger.

• 1] 112.8 km/h
• 2] 100.8 km/h
• 3] 80.16 km/h
• 4] 85.16 km/h
• 5] None of these