A man travel from A to B at 20 km/Hr. and come back from B to A at 30 km/hr. Find the average speed of the whole journey.

A car covers the first 35 km in 45 minutes and the remaining 69 km in 75 minutes. What is the average speed of the car?

Rehman walks at 8 km/hr and Roma cycles at 13 km/hr towards each other. What was the distance between them when they started if they meet after 36 minutes?

A and B start at the same time with speeds of 40 km/hr and 50 km/hr respectively. If in covering the journey A takes 15 minutes longer than B, the total distance of the journey is

The distance between two points A and B is covered in $$ {5{1\over 2}\ hours}$$ at a speed of 50 km/hr. If the speed in increased by 5km/hr, how much time would be saved?

Ratio of speed of boat in down stream and speed of stream is 9:1, if speed of current is 3 km per  hr, then find distance travelled(in km) upstream in 5 hours.

A bullet travels at 750 m/s. How long will it take to travel 1 km?

Ravi drove for 4 hours at a speed of 70 miles per hour and for 2 hours at 40 miles per hour. What was his average speed (in miles per hour) for the whole journey?