Distance between Ranjan and Gomes house is 9km. Ranjan has to attend Gomes birthday party at 7 o'clock. He started from his home at 6 o'clock on his bicycle and covered a distance of 6km in 40 minutes. At that point he met David and he spoke to him for 5minutes and reached Gomes birthday party at 7 o'clock. At what speed did he cover the second part of the journey? Calculate his average speed for the entire journey. Required to answer. Single line text.

Kindly check explanation

Explanation:

Given the following :

Distance between Ranjan and Gomez house = 9km

Start time = 6'o clock

Time he arrived at Gomes house = 7'o clock

Time used for chatting during this period = 5 minutes

Distance covered in 40minutes = 6km

Time spend for second part of the journey = (60 - (40 + 5))minutes = 15 minutes = 15/60 = 0.25 hoir

Distance covered during second part of journey = 9 - 6 = 3 km

Speed = distance / time

Speed = 3km / 0.25 hr = 12km/hr

Average speed for entire journey :

First part :

Speed = distance / time

Time = 40 minutes = (40/60) = 0.667 hour

Speed = 6km / 0.667 hour = 9km / hr

Average speed :

(First part + second part) / 2

(9km/hr + 12km/hr) / 2 = 21km/hr / 2 = 10.5 km/hr

= 10.5km/hr