Question 1. The distance between station A and B is 120 km. A train travelling at a speed can cover the distance in 2 hours 30 minutes. By how many km/h should the speed of the train be increased for it to take 30 minutes less to cover the distance.
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Solution 1.

Case 1:

Data given:

Distance between station A and B = 120 km

Time taken by the train = 2 h 30 minutes

=(2+30/60) h

=5/2 h

Speed S1 of the train in km/h = D/S

=120/(5/2)

=48 km/h

Case 2:

Distance between station A and B = 120 km

Time taken by the train = 2 h

Speed S2 of the train = 120/2

=60 km/h Increased speed (S2-S1) = (60-48) km/h

=12 km/h Ans.Question 2. Two trains start from the same staion in the smae direction. The speed of the first train is 70 km/h and that of the second train is 20 m/s. 1) Which train is moving faster ?

2) What is the distance between the trains after 1 hour and 15 minutes ?

Answer 2. Speed of the first train = 70 km/h

Speed of the second train = 20 m/s

i)Speed of the second train in km/h= 20x(…

Solution 1.

Case 1:

Data given:

Distance between station A and B = 120 km

Time taken by the train = 2 h 30 minutes

=(2+30/60) h

=5/2 h

Speed S1 of the train in km/h = D/S

=120/(5/2)

=48 km/h

Case 2:

Distance between station A and B = 120 km

Time taken by the train = 2 h

Speed S2 of the train = 120/2

=60 km/h Increased speed (S2-S1) = (60-48) km/h

=12 km/h Ans.Question 2. Two trains start from the same staion in the smae direction. The speed of the first train is 70 km/h and that of the second train is 20 m/s. 1) Which train is moving faster ?

2) What is the distance between the trains after 1 hour and 15 minutes ?

Answer 2. Speed of the first train = 70 km/h

Speed of the second train = 20 m/s

i)Speed of the second train in km/h= 20x(…