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3 years ago

A train travels 65 kilometers in 5 hours, and then 61 kilometers in 4 hours. What is its average speed? _______km/hr

Physics

2 answers:

olasank [31]3 years ago

4 0

The trains average speed is 13 km/hr.

Galina-37 [17]3 years ago

4 0

Yes, Average speed equals total distance divided by total time.

Total distance= 65km + 61km= 126 km

Total time= 5h + 4h = 9 h

126km/9h= 14km/h

The trains average speed is 14 km/h

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The Area of the triangle is given by $A=h\times b$ where $h=\sqrt{l^2-b^2}$ (by using the Pythagoras' Theorem) and $b$ is the length of the base of the triangle or the distance between the bottom of the ladder and the wall.

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$\frac{dA}{dt}=8\left(-\frac{1}{\sqrt{39^2-36^2}}\cdot 36^2+\sqrt{39^2-36^2}}\right)=-571.2\, ft^2/s$

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2 years ago

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