7. A car can finish a certain journey in 10 hours at the speed of 48 km/hr. By how much should its speed be increased so that it may take only 8 hours to cover the same distance.
Answers
Answer:
Step-by-step explanation:
Step-by-step explanation:
Given :-
A car can finish a certain journey in 10 hours at the speed of 48 km/hr.
To find :-
By how much should its speed be increased so that it may take only 8 hours to cover the same distance?
Solution :-
Given that
The speed of the car = 48 km/hr
Time taken by the car for finishing journey
= 10 hours
We know that
Distance = Speed × Time
=> D = 48×10 km
=> D = 480 km
Distance covered by the car = 480 km
Let the increasing in the speed be
X km/hr
The new speed of the car = (48+X) km/hr
The time taken for the journey at the speed of (48+X) km/hr = 8 hours
We know that
Distance = Speed × Time
=> 480 = (48+X)× 8
=> 480/8 = 48+X
=> 60 = 48+X
=> 48+X = 60
=> X = 60-48
=> X = 12 km/hr
The increasing in speed = 12 km/hr
Answer :-
The speed of the car should be increased to 12 km/hr more than the original speed of the car for finishing the same distance .
Used formulae :-
→ Distance = Speed × Time