A car travels 100 km at a speed of 60 km/h and returns with a speed of 40 km/h. Calculate the average speed for the whole journey.

Open in App

Solution

Time taken to go =hr =hr
Time taken to return = hr
Total distance = (100 + 100) km = 200 km
total time taken = ( $\frac{5}{3}$ + $\frac{5}{2}$ )hr = hr
average speed = $fraction numerator t o t a l space d i s tan c e over denominator t o t a l space t i m e end fraction$
= $fraction numerator 200 over denominator begin display style 25 over 6 end style end fraction fraction numerator 200 cross times 6 over denominator 25 end fraction$

= 48 km/hr
Hence, the average speed is 48 km/hr.

Suggest Corrections

374

Similar questions

Q. A car travels

100 k m

at a speed of

60 k m / h

and returns with a speed of

40 k m / h

. Calculate speed for the hole journey.

a) A train travels a distance with a speed of 40 km/h and returns with a speed of 60 km/h. Calculate the average speed of the train.

b) On a 60 km track, a train travels the first 30 km at a uniform speed of 30 km/h. How fast must a train travel the next 30 km so that the average speed is 40 km/hr for the entire trip?

Q. A car goes down a certain road at an average speed of

40 k m / h

and returns along the same road at an average speed of

60 k m / h

. Calculate the average speed for the round trip. (in km/h)

Q. A car travels from

A

B

at a speed of

20 km/h

and returns at a speed of

30 km/h

. The average speed of the car for the whole journey is

Join BYJU'S Learning Program

A car travels 100 km at a speed of 60 km/h and returns with a speed of 40 km/h. Calculate the average speed for the whole journey.

Time taken to go =hr =hr Time taken to return = hr Total distance = (100 + 100) km = 200 km total time taken = (53 + 52)hr = hr average speed = = = 48 km/hr Hence, the average speed is 48 km/hr.