Quiz Discussion

An athlete runs 200 meters race in 24 seconds. His speed in km/h is

• 1] 20
• 2] 24
• 3] 28.5
• 4] 30

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

A person travels three equal distance at a speed of x km/hr, y km/hr and z km/hr respectively. What is the average speed for the whole journey ?

• 1]

  \(\frac{{xyz}}{{3\left( {xy + yz + zx} \right)}}\)    km/hr

• 2]

  \(\frac{{xyz}}{{\left( {xy + yz + zx} \right)}}\)    km/hr

• 3]

  \(\frac{{\left( {xy + yz + zx} \right)}}{{xyz}}\)    km/hr

• 4]

  \(\frac{{3xyz}}{{\left( {xy + yz + zx} \right)}}\)    km/hr

Ravi walks to and fro to a shopping mall. He spends 30 minutes shopping. If he walks at a speed of 10 km an hour, he returns home at 19.00 hours. If he walks at 15 km an hour, her returns home at 18.30 hours. How far must he walk in order to return home at 18.15 hours ?

• 1] 17 km/hr
• 2] 17.5 km/hr
• 3] 18 km/hr
• 4] 19 km/hr
• 5] None of these

A runs \(\frac{7}{4}\) times as fast as B. If A gives B a start of 300 m, how far must the winning post be if both A and B have to end the race at the same time?

• 1] 1400 m
• 2] 700 m
• 3] 350 m
• 4] 210 m

A train met with an accident 120 km from station A. It completed the remaining journey at \(\frac{5}{6}\) of its previous speed and reached 2 hours late at station B. Had the accident taken place 300 km further, it would have been only 1 hour late. What is the speed of the train?

• 1] 100 km/h
• 2] 12 km/h
• 3] 60 km/h
• 4] 50 km/h

A boy rides his bicycle 10 km at an average speed of 12 km/hr and again travels 12 km at an average speed of 10 km//hr. His average speed for the entire trip is approximately:

• 1] 10.4 km/hr
• 2] 10.8 km/hr
• 3] 11 km/hr
• 4] 12.2 km/hr

A train travels at a speed of 30 km/hr for 12 minutes and at a speed of 45 km/hr for the next 8 minutes. The average speed of the train for this journey is :

• 1] 30 km/hr
• 2] 36 km/hr
• 3] 37.5 km/hr
• 4] 48 km/hr

An aeroplane flies twice as fast as a train which covers 60 miles in 80 minutes. What distance will the aeroplane cover in 20 minutes ?

• 1] 30 miles
• 2] 35 miles
• 3] 40 miles
• 4] 50 miles

A ship leaves on a long voyage. When it is 18 miles from shore, a sea plane, whose speed is ten times that of the ship, is sent to deliver mail. How far from the shore does the sea plane catch up with the ship?

• 1] 24 miles
• 2] 25 miles
• 3] 22 miles
• 4] 20 miles
• 5] None of these