# Raja travelled 2/5 of his journey at 50 km/h. The next 1/5 of his journey he travelled at 40 km/h. The remaining 40 km he covered in half an hour. How much time did he take for the whole journey?

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by raviTambe15

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by raviTambe15

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Solution:

Let the Total distance Of Journey = X km

Speed for traveling ( 2/5 )*X = 50 km /hr

Speed for traveling (1/5)*X = 40 km / hr

Remaining distance = 40 km

We know that remaining Distance = X - 2/5*X - 1/5*X

= X (1-2/5 - 1/5)

= X ( 1 - 3/5 )

= 2/5*X

2/5 *X = 40

X = 5/2 *40

X= 100 km

Therefore Total Distance Of Journey = 100 KM

hence , The Persons Travels first 40 km of his journey with a speed of 50 Km/ hr , next 20 Km with the speed of 40 Km / hr and the last 40 Km in half an Hour .

Therefore the Total time taken by him to complete journey = (40 / 50 + 20 /40 + 0.5 )hrs

NOte :-

Speed = distance / time ;

=> time = distance / speed

That's why I used 40 / 50 and 20 / 40 in calculating the time taken to travel the first 40 km and 20 km of the journey.

= (0.8 + 0.5 + 0 .5 )hrs

= 1.8 hrs

Hope this is helpful!!

Solution:

Let the Total distance Of Journey = X km

Speed for traveling ( 2/5 )*X = 50 km /hr

Speed for traveling (1/5)*X = 40 km / hr

Remaining distance = 40 km

We know that remaining Distance = X - 2/5*X - 1/5*X

= X (1-2/5 - 1/5)

= X ( 1 - 3/5 )

= 2/5*X

2/5 *X = 40

X = 5/2 *40

X= 100 km

Therefore Total Distance Of Journey = 100 KM

hence , The Persons Travels first 40 km of his journey with a speed of 50 Km/ hr , next 20 Km with the speed of 40 Km / hr and the last 40 Km in half an Hour .

Therefore the Total time taken by him to complete journey = (40 / 50 + 20 /40 + 0.5 )hrs

NOte :-

Speed = distance / time ;

=> time = distance / speed

That's why I used 40 / 50 and 20 / 40 in calculating the time taken to travel the first 40 km and 20 km of the journey.

= (0.8 + 0.5 + 0 .5 )hrs

= 1.8 hrs