Quiz Discussion

A train running at a speed of 54 km/hr crosses a platform in 30 seconds. The platform is renovated and its length is doubled. Now, the same train running at same speed crosses the platform in 46 seconds. Find the length of the train.

• 1] 180 metres
• 2] 200 metres
• 3] 210 metres
• 4] 240 metres
• 5] 450 meters

The distance between two places R and S is 42 km. Anita starts from R with a uniform speed of 4 km/hr towards S and at the same time Romita starts from S towards R also with some uniform speed. They meet each other after 6 hours. The speed of Romita is :

• 1] 18 km/hr
• 2] 20 km/hr
• 3] 3 km/hr
• 4] 8 km/hr

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

Due to the technical snag in the signal system two trains start approaching each other on the same track from two different stations, 240 km away each other. When the train starts a bird also starts moving to and fro between the two trains at 60 kmph touching each train each time. The bird initially sitting on the top of the engine of one of the trains and it moves so till these trains collide. If these trains collide one and half hour after start, then how many kilometers bird travels till the time of collision of trains?

• 1] 90 km
• 2] 130 km
• 3] 120 km
• 4] 95 km
• 5] None of these

In a race of 200 metres, B can give a start of 10 metres to A and C can give a start of 20 metres to B. The start that C can give to A, in the same race, is :

• 1] 30 metres
• 2] 25 metres
• 3] 29 metres
• 4] 27 metres

Points 'A' and 'B' are 70 km apart on a highway and two cars start at the same time. If they travel in the same direction, they meet in 7 hours, but if they travel towards each other they meet in one hour. Find the speed of the two cars (in km/hr).

• 1] 20, 30
• 2] 40, 30
• 3] 30, 50
• 4] 20, 40

Three runners A, B and C run a race, with runner A finishing 12 metres ahead of runner B and 18 metres ahead of runner C, in another race of same type runner B finished 8 metres ahead of runner C. Each runner travels the entire distance at a constant speed. The length of the race is :

• 1] 36 metres
• 2] 48 metres
• 3] 60 metres
• 4] 72 metres

Gautam goes office at a speed of 12 kmph and return homes at 10 kmph. His average speed is :

• 1] 11 km/hr
• 2] 22 km/hr
• 3] 10.9 km/hr
• 4] 12.5 km/hr

A man covers a total distance of 100 km on bicycle. For the first 2 hours, the speed was 20 km/hr and for the rest of the journey, it came down to 10 km/hr. The average speed will be :

• 1]

  \(12\frac{1}{2}\) km/hr

• 2]

  13 km/hr

• 3]

  \(\frac{1}{8}\) km/hr

• 4]

  20 km/hr

A car traveling with \(\frac{5}{7}\) of its usual speed covers 42 km in 1 hr 40 min 48 sec. What is the usual speed of the car?

• 1]

  \(17\frac{6}{7}\) km/hr

• 2]

  35 km/hr

• 3]

  25 km/hr

• 4]

  30 km/hr