if a train runs at 40kmph it reaches its destination late by 11 minutes , but if it runs at 50 kmph it is late by 5 minutes only. find the distance to be covered by the train. please answer this question with explanation
Answers
If a train runs at 40 km/hr it reaches it's destination late by 11 minutes
If it runs at 50 km/hr it is late by 5 minutes
The distance to be covered by the train.
Let train take x hr to reach the destination.
11 minute = 11/60 hr and
5 minute = 5/60 hr
Distance = Time × Speed
It's late means it take more time than the required time.
According to the first condition.
Distance = ( x + 11/60 ) × 40
=> Distance = 40x + 22/3...(1)
According to the second condition.
Distance = ( x + 5/60 ) × 50
=> Distance = 50x + 25/6...(2)
From equation (1) and (2), we get
=> 40x + 22/3 = 50x + 25/6
=> 10x = 22/3 - 25/6
=> 10x = (44-25)/6
=> 10x = 19/6
=> x = 19/60
Substituting in equation (1), we get
=> Distance = 40( 19/60 ) + 22/3
=> Distance = 38/3 + 22/3
=> Distance = 60/3
=> Distance = 20 km
The distance to be covered by the
train is 20 km
Step-by-step explanation:
Let x be the constant duration.
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STEP 1: Find distance for the train that runs at 40kmph,
The train travels at 40km/h
The train is 11 mins late
⇒ duration = x + 11/60 hours
.
Distance = Speed x Time
Distance = 40(x + 11/60)
Distance = (40x + 22/3) km
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STEP 2: Find distance for the train runs at 50kmph:
The train travels at 50 km/h
The train is 5 mins late
⇒ duration = x + 5/60 hours
⇒ duration = x + 1/12 hours
.
Distance = Speed x Times
Distance = 50(x + 1/12)
Distance = (50x + 25/6) km
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STEP 3: Find x:
Since both the travel the same distance:
40x + 22/3 = 50x + 25/6
50x - 40x = 22/3 - 25/6
10x = 19/6
x = 19/60
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STEP 4: Find distance:
Distance = 40x + 22/3
Distance = 40(19/60) + 22/3
Distance = 20 km
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Answer: The distance is 20 km