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2 years ago

A train 360 m long is running at a speed of 45 km/hr. In what time will it pass a bridge 140 m long?.

Mathematics

1 answer:

natali 33 [55]2 years ago

8 0

The train will pass a bridge in 40 seconds.

<h3>What is the distance?</h3>

Distance is defined as the product of speed and time.

Given that A train 360 m long is running at a speed of 45 km/hr.

Speed of train = 45 km/hr.

And it passes a bridge 140 m long.

Length of train = 360 meters

Since 1 km = 1000 meters.

and 1 hour = 3600 seconds

we have to determine the length of the train

So 1(km/hr.) = (1000/3600) = (26/72) meter/seconds

45 km/hr = 45 ×5/18 = 25/2 meter per second

So the speed of the train = 25/2 meters per second

Total distance to be covered = (360+140)m = 500m.

So time will it pass a bridge = distance/speed

Substitute the values of distance and speed in the above formula,

⇒ 500/(25/2)

⇒ 500×2/25

⇒ 40 seconds

Hence, the train will pass a bridge in 40 seconds.

Learn more about the distance here:

brainly.com/question/13269893

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Step-by-step explanation:

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<em>Rough work</em>

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Adding inside the bracket of $-6(x^2 - \frac{x}{2})$ to give: $-6(x^2 - \frac{x}{2} + \frac{1}{4})$

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The expression becomes

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Make y the subject of formula

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