On a 60 km straight road, a bus travels the first 30 km with a uniform speed of 30 kmh-1. How fast must the bus travel the next 30 km so as to have average speed of 40 kmh-1 for the entire trip?
Answers
Answer:
Therefore bus should travel next 30km distance at a speed of 60 km/h. Hope this helps u!
Given :
→ Total distance to be covered = 60 km
→ A bus travels the first 30 km with a uniform speed of 30 km/h
→ Average speed for the entire trip = 40 km/h
To find :
→ Speed of the bus for the next 30 km
Solution :
Using formula,
→ Average speed = Total distance travelled ÷ Total time taken
Substituting the given values :-
→ 40 = 60 ÷ Total time taken
→ 60 ÷ 40 = Total time taken
→ 6 ÷ 4 = Total time taken
→ 3/2 = Total time taken
Therefore, the total time taken = 3/2 hours
Now calculating the time taken for the first 30 km :-
Using formula,
→ Time = Distance ÷ Speed
we have,
• Distance = 30 km
• Speed = 30 km/h
Substituting the given values :-
→ Time = 30/30
→ Time = 1
Therefore, time = 1 hour
Now, calculating the time for the next 30 km :-
Using formula,
→ Time = Distance ÷ Speed
we have,
• Distance = 30 km
• Speed = x [We don't have the value of speed, so we will suppose it as x.]
→ Time = 30/x hours
Total time taken = Time taken to cover first 30 km + Time taken to cover next 30 km
→ 3/2 = 1 + 30/x
→ 3/2 - 1 = 30/x
→ (3 - 2)/2 = 30/x
→ 1/2 = 30/x
→ x = 30 × 2
→ x = 60
Therefore, the speed of the bus for the next 30 km = 60 km/h