A train travels a distance of 480 km at a uniform speed. If the speed had been 8 km/hr less, then it would have taken 3 hours more to cover the same distance. The original speed of the train is?
By BYJU'S Exam Prep
Updated on: September 25th, 2023
A train travels a distance of 480 km at a uniform speed. If the speed had been 8 km/hr less, then it would have taken 3 hours more to cover the same distance. The original speed of the train is?
The average speed of a train can be calculated by dividing the total distance covered by the train and the time taken by the train to cover the distance. By applying this formula one can find that the original speed of the train is 40 km/hr.
Table of content
Distance of Train
The total motion covered by the train regardless of the direction is known as Distance. The distance can be described as how much distance the train covered despite any start or end point.
Speed of Train
Speed is a measurable quantity that measures the ratio of the distance traveled by train to the time required to travel that distance. Speed is divided into four types- Uniform, Variable, Instantaneous and Average Speed.
Time of Train
Time can be stated as the dimension based on the advancement of any system. The SI unit of time is seconds. Time can be expressed as seconds, minutes, hours, days, weeks, months, and years.
Solution
Let the original speed be v km/hr
Let’s assume that it covers 480 km in time t hrs
So,
Speed = Distance/ Time
Equation 1: V = 480/t
If it travels at a speed of 8km/hr, it takes 3 more hours to cover the same distance
Equation 2: V-8= 480/ t+3 = v= (480/t+3 +8)
Equating equations 1 and 2
480/t+3 + 8 = 480/t
480/t+3 = 480/t-8 = 480-8t/t
480t = (480 – 8t) (t+3)
480t = 480t + 1440 – 8t2 – 24t
8t2 +24t – 1440 = 0
t2 + 3t – 180 = 0
(t-15)(t+12) = 0
t = – 15 or 12
As time cannot be negative, t= 12 hrs
Hence,
v= 480/t = 480/12 = 40 km/hr
The original speed of the train is 40 km/hr
Summary
A train travels a distance of 480 km at a uniform speed. If the speed had been 8 km/hr less, then it would have taken 3 hours more to cover the same distance. The original speed of the train is?
A train travels a distance of 480 km at a uniform speed. If the speed had been 8 km/hr less, then it would have taken 3 hours more to cover the same distance. The original speed of the train is 40 km/hr.
Related Questions
- Find five rational numbers between 3/5 and 4/5
- In Indian rupees, 1 trillion is equal to how many crores?
- Find the Probability of a Leap Year having 53 Sundays
- Write Five Uses Of Convex Mirror
- What Are The First 30 Elements?
- The traffic lights at three different road crossings change after every 48 seconds, 72 seconds, and 108 seconds respectively. If they change simultaneously at 7 a.m. at what time will they change simultaneously again?
- A bus decreases its speed from 80 km/hr to 60 km/hr in 5s, find the acceleration of the bus
