Naina and Eesha, track stars with superb hearing, ran as fast as they could to catch up to the ice cream truck in the next town over. They averaged 6 kms per hour, then rested to enjoy their ice cream. They averaged 4 kms per hour over the same distance on the way back. Not counting the time they rested, What was their average speed?
4.8 km/h
If the distance is x, then they spent x/6 hrs on one direction and x/4 hrs on the way back Total distance= 2x Total time= x/6+x/4= 5x/12 Average speed= 2x: 5x/12= 24/5= 4.8 km/h
A racing driver drove around a 6 km track at 140 km/hr for 3 km, 168 km/hr for 1.5 km and 210 km/hr for 1.5 km. What was his average speed for the entire 6 km?
A cyclist covers his outward journey at 15 mph.
The return, over exactly the same distance, is uphill. He completes it at 5 mph.
What is the cyclist's average speed over the entire journey?
An aeroplane covers its outward journey at 600 kmph.
It returns, over exactly the same distance, at 400 kmph.
What is the average speed of the aeroplane over the entire journey?
A car covers its outward journey at 66 mph.
It returns, over exactly the same distance, at 33 mph.
What is the car's average speed over the entire journey?
Early one morning a family travelled to a shopping centre at 35 km/h.
After a day of Christmas shopping they returned, over exactly the same distance, at a crawl of only 14 km/h.
What was their average speed over the entire journey?