1.

A train travels at a certain average speed for a distance of 63 km and then travels a distance of 72 km at an average speed of 6 km/hr more than its original speed. If it takes 3 hours to complete the total journey, what is the original speed of the train in km/hr?1. 602. 543. 424. 36

Answer» Correct Answer - Option 3 : 42

Given:

A train travels at a certain average speed for a distance of 63 km

Then travels a distance of 72 km at an average speed of 6 km/hr. more than its original speed.

It takes 3 hours to complete the total journey

Total distance:63 + 72 = 135 km

Total time = 3 hr.

Speed = Distance/Time

Using formula;

Speed is equal to 45 km/hr.

The Sum of time for completing 63 km and 72 km must be equal to 3 hr. or 180 min

Now, using the option

1)

60 km/h

Time for 63 km:63/60 = 1.05 hr.

Time for 72km: 72/66= 1.09hr

Not equal to 3 hr.

2)

54 km/hr

Time for 63 km:63/54= 1.16hr.

Time for 72km: 72/60= 1.2hr

Not equal to 3 hr.

3)

42 km/hr.

Time for 63 km:63/42= 1.5hr.

Time for 72km: 72/48= 1.5hr

Equal to 3 hr.

Hence, Original speed is 42 km/hr.



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