On a 100km round trip, Jessica averages 40 km/h to her destination and 60km/h returning. What is the average speed for the entire trip
Mathematics · High School · Mon Jan 18 2021
Answered on
Given :
Total distance = 100 km
Distance on one side = 50 km
Speed of reaching destination = 40 km/h
Speed of returning = 60 km/h
So, Time = distance/speed
T1 = 50/40
= 1.25 hr or 75 minutes
T2 = 50/60
= 0.83 hr or 50 minutes
So, Total Time = (75 + 50)min
= 125 minutes or 25/12 hr
So, Average Speed = Total distance/Total time
= 100km/25/12 hr
= 100km × 12 /25hr
= 48 km/hr
Thus, average Speed of the entire trip is 48 km/hr