Question : The diameter of each wheel of a car is 70 cm. If each wheel rotates 400 times per minute, then the speed of the car (in km/hr) is: (Take $\pi=\frac{22}{7}$)

Option 1: 0.528

Option 2: 528

Option 3: 52.8

Option 4: 5.28

Question : A car covers a certain distance in 25 hours. If it reduces the speed by $\frac{1}{5}$th, the car covers 200 km less in that time. The speed of the car is:

Option 1: 60 km/hr

Option 2: 30 km/hr

Option 3: 40 km/hr

Option 4: 50 km/hr

Question : A car travels the first 160 km at a speed of 64 km/hr and the next 160 km at a speed of 80 km/hr. What is the average speed for the first 320 km of the tour?

Option 1: 70 km/hr

Option 2: 71.11 km/hr

Option 3: 66 km/hr

Option 4: 75.32 km/hr

Question : A person travels 600 km by train at 80 km/hr, 800 km by ship at 40 km/hr, 500 km by aeroplane at 400 km/hr, and 100 km by car at 50 km/hr. What is the average speed for the entire distance?

Option 1: $65\frac{5}{123}$ km/hr

Option 2: 60 km./hr.

Option 3: $60\frac{5}{123}$ km/hr

Option 4: 62 km./hr.

Question : A car moving in the morning fog passes a man walking at 4 km/hr in the same direction. The man can see the car for 3 minutes and visibility is up to a distance of 130 m. The speed of the car is:

Option 1: $7\frac{3}{5}$ km/hr

Option 2: $6\frac{3}{5}$km/hr

Option 3: $7$ km/hr

Option 4: $5$ km/hr

Question : A car can finish a certain journey in 10 hours at a speed of 42 km/hr. In order to cover the same distance in 7 hours, the speed of the car (km/hr) must be increased by:

Option 1: 12 km/hr

Option 2: 15 km/hr

Option 3: 18 km/hr

Option 4: 24 km/hr