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A train travels 63 kilometers in 2 hours, and then 56 kilometers in 3 hours. What is its average speed? i need the answer and units please

User Bslima
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1 Answer

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The average speed is the ratio between the total space and the total time of the motion:

v= (S_(tot))/(t_(tot))
The total space is

S_(tot)=63 km + 56 km = 119 km
while the total time is

t_(tot)=2h+3h = 5h
So, the average velocity is

v= (119 km)/(5 h) =23.8 km/h

We can also rewrite it in m/s. The total space is
S_(tot)=119000 m, while the time is
t_(tot)=5h\cdot 3600 s/h = 18000s, and so

v= (119000m)/(18000s)=6.6 m/s
User Gevra
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