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.

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?

A car runs first 275 km at an average speed of 50 km/h and the next 315 km at an average speed of 70 km/h. What is the average speed (in km/h) for the entire journey?

A takes 2 hours more than B to cover a distance of 40 km. If A doubles his speed, he takes $$1{1\over 2} $$ hours more than B to cover 80 km. To cover a distance of 90 km, how much time will B take travelling at his same speed?

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?

How many kilometers will a cyclist cover in 2 hours 20 minutes with a speed of 5 meters per second?

A man can row at 7 km/hour in still water. He finds that it takes twice the time to row upstream than the time to row downstream. The speed of the stream is

If a person travels a certain distance at a speed of 10 km/h, and returns through the same route at a speed of 20 km/h, then what will be the average speed during the whole journey?