Quiz Discussion

Two cars are moving with speed v1, v2 towards a crossing along two roads, If their distance from the crossing be 40 metres and 50 metres at an instant of time then they do not collide if their speeds are such that :

• 1]

  v1 : v2 =16 : 25

• 2]

  v1 : v2 e 4 : 5

• 3]

  v1 : v2 e 5 : 4

• 4]

  v1 : v2 e 25 : 16

A bus moving at a speed of 45 km/hr catches a truck 150 metres ahead going in the same direction in 30 seconds. The speed of the truck is :

• 1] 27 km/hr
• 2] 24 km/hr
• 3] 25 km/hr
• 4] 28 km/hr

A certain distance is covered at a certain speed. If half of this distance is covered in double the time, the ratio of the two speed is :

• 1] 1 : 16
• 2] 4 : 1
• 3] 2 : 1
• 4] 1 : 4

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 and B travel the same distance at speed of 9 km/hr and 10 km/hr respectively. If A takes 36 min more than B, the distance travelled by each is :

• 1] 48 km
• 2] 54 km
• 3] 60 km
• 4] 66 km

Two planes move along a circle of circumference 1.2 kms with constant speeds. When they move in different directions, they meet every 15 seconds and when they move in the same direction one plane overtakes the other every 60 seconds. The speed of the slower plane is :

• 1] 0.02 km/sec
• 2] 0.03 km/sec
• 3] 0.04 km/sec
• 4] 0.05 km/sec

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

The speed of a motor-boat is that of the current of water as 36:5. The boat goes along with the current in 5 hours 10 minutes. It will come back in:

• 1] 5 hours 50 minutes
• 2] 6 hours
• 3] 6 hours 50 minutes
• 4] 12 hours 10 minutes

A man can walk uphill at the rate of \(2\frac{1}{2}\) km/hr and downhill at the rate of \(3\frac{1}{4}\) km/hr. If the total time required to walk a certain distance up the hill and return to the starting point was 4 hr 36 min, then what was the distance walked up the hill by the man ?

• 1]

  4 km

• 2]

  \(4\frac{1}{2} \)km

• 3]

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

• 4]

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

A motor boat takes 2 hours to travel a distance of 9 km downstream and it takes 6 hours to travel the same distance against the current. The speed of the boat in still water and that of the current (in km/h) respectively are:

• 1] 6, 5 km/h
• 2] 3, 1.5 km/h
• 3] 8, 5 km/h
• 4] 9, 3 km/h