Quiz Discussion

In a flight of 6000 km, an aircraft was slowed down due to bad weather. The average speed for the trip was reduced by 400 kmph and the time of flight increased by 30 minutes. The original planned duration of the flight was :

• 1]

  \({2\frac{1}{2}}\) hours

• 2]

  \({3\frac{1}{3}} \)hours

• 3]

  \({4\frac{1}{3}}\) hours

• 4]

  \({5\frac{1}{3}}\) hours

Starting from his house one day,a student walks at a speed of 2.5 kmph and reaches his house 6 minutes late.Next day he increases his speed by 1kmph and reaches school 6 minutes early.How far is the school from his house.

• 1]

  7/4 km

• 2]

  3/2 km

• 3]

  4/5 km

• 4]

  1/2 km

A car takes 15 minutes less to cover a distance of 75 km, if it increases its speed by 10 km/hr from its usual speed. How much time would it take to cover a distance of 300 km using this speed ?

• 1]

  5 hrs

• 2]

  \(5\frac{1}{2}\) hrs

• 3]

  6 hrs

• 4]

  \(6\frac{1}{2}\) hrs

A girl while walking diametrically across a semicircular playground, takes 3 minutes less than if she had kept walking round the circular path from A to B. If she walks 60 metres a minute, what is diameter of the play ground?

• 1] 60 m
• 2] 48 m
• 3] 84 m
• 4] 315 m
• 5] None of these

The speed \(3\frac{1}{3}\) m/sec when expressed in km/hr becomes :

• 1] 8 km/hr
• 2] 9 km/hr
• 3] 10 km/hr
• 4] 12 km/hr

An athlete claimed that his timing for a 100 m dash should be corrected because the starting signal was gives by a gun fired from a point 10 m away from him and the timekeeper was standing close to the gun. The error due to this could be (in seconds) :

• 1] 0.03 sec
• 2] 0.1 sec
• 3] 0.5 sec
• 4] 0.7 sec

A person wishes to reach his destination 90 km away 3 hours but for the first half of the journey his speed was 20 km/hr. His average speed for the rest of the journey should be :

• 1] 4 km/hr
• 2] 0.75 km/min
• 3] 1 km/min
• 4] None of these

Deepa rides her bike at an average speed of 30 km/hr and reaches her destination in 6 hours. Hema covers the same distance in 4 hours. If Deepa increases her average speed by 10 km/hr and Hema increases her average speed by 5 km/hr, what would be the difference in their time taken to reach the destination ?

• 1] 40 min
• 2] 45 min
• 3] 54 min
• 4] 1 hr
• 5] None of these

Karan and Arjun run a 100 metre race, where Karan beats Arjun by 10 metre. To do a favour to Arjun, Karan starts 10 metre behind the starting line in a second 100 race. They both run at their earlier speeds. Which of the following is true in connection with the race?

• 1] Karan and Arjun reach the finishing line simultaneously
• 2] Arjun beats Karan by 1 metre
• 3] Arjun beats Karan by 11 metre
• 4] Karan beats Arjun by 1 metre
• 5] Cannot be said

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