Quiz Discussion

A candle of 6 cm long burns at the rate of 5 cm in 5 hour and an another candle 8 cm long burns at the rate of 6 cm in 4h. What is the time required to each candle to remain of equal lengths after burning for some hours, when they starts to burn simultaneously with uniform rate of burning?

• 1] 1 hours
• 2] 1.5 hours
• 3] 2 hours
• 4] 3 hours
• 5] 4 hours

A train approaches a tunnel AB. Inside the tunnel is a cat located at a point that is \(\frac{3}{8}\) of the distance AB measured from entrance A. When the train whistles, that cat runs. If the cat moves to entrance A of the tunnel, the train catches the cat exactly at the entrance. If the cat moves to exit B, the train catches the cat at exactly the exit. The ratio of the speed of the train to that of the cat is of the order :

• 1] 3 :1
• 2] 4 : 1
• 3] 5 : 1
• 4] None of these

Rani goes to school from her house in 30 minutes. Raja takes 45 minutes in covering the same distance. Find the ratio between time taken by Rani and Raja ?

• 1] 2 : 3
• 2] 4 : 3
• 3] 3 : 2
• 4] 1 : 3

A car travels from P to Q at a constant speed. If its speed were increased by 10 km/hr, it would have taken one hour lesser to cover the distance. It would have taken further 45 minutes lesser if the speed was further increased by 10 km/hr. The distance between two cities is :

• 1] 540 km
• 2] 420 km
• 3] 600 km
• 4] 620 km

The speed of electric train is 25% more than that of steam engine train. What is the time taken by an electric train to cover a distance which a steam engine takes 4 hours 25 minutes to cover ?

• 1]

  \(3\frac{1}{10}\) hrs

• 2]

  \(3\frac{11}{15}\) hrs

• 3]

  \(3\frac{11}{12}\) hrs

• 4]

  \(3\frac{8}{15}\) hrs

A postman goes with a speed of 36 km/h what is the speed of postman in m/s?

• 1] 4.5 m/s
• 2] 6 m/s
• 3] 5 m/s
• 4] 10 m/s

Vinay and Versha run a race with their speed in the ratio of 5 : 3. They prefer to run on a circular track of circumference 1.5 km. What is the distance covered by Vinay when he passes Versha for the seventh time?

• 1] 25.25 km
• 2] 26.25 km
• 3] 13.2 km
• 4] 14.5 km

A star is 8.1 × 1013 km away from the earth. Suppose light travels at the speed of 3.0 × 105 km per second. How long will it take the light from the star to reach the earth ?

• 1] 7.5 × 103 hours
• 2] 7.5 × 104 hours
• 3] 2.7 × 1010 seconds
• 4] 2.7 × 1011 seconds

A jeep is chasing a car which is 5 km ahead. Their respective speeds are 90 km/hr and 75 km/hr. After how many minutes will the jeep catch the car ?

• 1] 10 min
• 2] 20 min
• 3] 24 min
• 4] 25 min

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