Problem Solving Example
1) If a train cross the 150 km in just 3 hours then find the speed in km/h
Ans.) If, a train takes 3 hours covers 150 km
By, 1 hours = 150/3 = 50 km/h (Ans.)
2) If a train’s speed is 60 Km/h then this train how far will go by 5 hours ?
Ans.) If, train in 1 hour can cross or cover 60 km distance
By 5 hours train can cross or cover = 60 Km X 5 h = 300 Km (Ans.)
3) If a train cross 200 meters in 10 minutes then what is the speed of this train ?
Ans.) As we know that, the speed of train can be measured according to per hour basics
So, by 10 minutes train cross 200 miters
1 minutes train cross 200 ÷ 10 = 20 miters
Then by, 1 hour = 60 minutes train cross 20 X 60 = 1200 miters
= 1200 meters/1000 meters = 1.20 km
So, the speed of the said train is 1.20 Km/h (Ans.)
4) The speed of a car is 45 Km/h, find it’s speed in m/s.
Ans.) As we all know 1 Km = 1000 m
So, 45 Km = 45000 m
1 Hour = 60 minutes
1 minutes = 60 seconds
So, 1 hour = 60 X 60 = 3600 seconds
So, if the car by 3600 seconds can move 45000 meters
1 second = 45000 / 3600 = 12.5 meters/s (Ans.)
5) If a train takes 6 hours to complete a journey at a speed of 72 km/h, how long will another train take to complete the same journey if it’s speed is 15 m/s.
Ans.) as per the given condition the second train speed is 15 m/s
So, now we have to convert the speed via Km/h
15 m = 15 / 1000 = 0.015 Km (as we know that, 1000 miters = 1 Km)
So, if the train by 1 second can cross = 0.015 Km
3600 seconds can cross = 0.015 X 3600 = 54 Km/h
Now, If the first train by 1 hour can cross 72 km
Then, by 6 hours can cross = 72 X 6 = 432 km
If the other train can cross 54 Km by 1 hour
Then, can cross 1 Km by 1/54 hour
432 km can cross by = 432 / 54 = 8 hours
So, the second train will take 8 hours to achieve the same distance that the first train has covered. (Ans.)