Question

Distance between Bholu's and Golu's house is 12 km. Bholu has to attend Golu's birthday party at 6:30 pm. He started from his home at 5 pm on his bicycle and covered the distance 6 km in 45 minutes. At that point, he met Chintu and he spoke to him for 15 minutes and reached Golu's birthday party at 6:30 pm. With what speed did he cover the second part of journey? Calculate his average speed for his entire journey?

Answer 1

It is given that Bholu has to attend the party at 6:30 pm

Total time spend by Bholu = 45 min (travelling) + 15 min (chatting) = 60 min

So Bholu has to reach Golu’s house within 30 min (1 hour and 30 min – 60 min)

The speed with which Bholu has to cover the second part of the journey is;
Speed = 6 km/30 min
and we know that, 60 mins = 1 h
then, 1 min = 1/60 h
so, 30 min = 30/60 h
thus, speed in km/h = $\frac{6\times 60}{30}km/h=12km/h$

The average speed of Bholu in the entire journey is total distance divided by the total time taken.

Average speed =Total distance travelled / Total time taken

$=\frac{12km}{1.5h}=8km/h$