Two bicycle riders made a 30 km trip in the same time. cyclist a traveled continuously at an average speed of 20 km/h. cyclist b traveled continuously except for a 20 min. rest break. what was b’s average speed for the time of actual riding ?

Answer : The average speed of cyclist B is 25.714 km/hr

Explanation :

First we have to convert average speed from km/hr to m/s.

Conversion used :

As we are given the average speed of cyclist A 20 km/hr. The average speed in m/s is:

As,

So,

Now we have to calculate the time taken by cyclist A to travel the distance.

conversion used : (1 min = 60 sec)

As per question, cyclist B travels same distance in same time but he took rest for 20 min. That means,

Time taken by cyclist B = 90 min - 20 min = 70 min

Now we have to calculate the average speed of cyclist B.

conversion used : (1 hr = 60 min)

Therefore, the average speed of cyclist B is 25.714 km/hr

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