Velocity equation

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How long will it take a motorist going at an average speed of 12 km per hour to complete a journey of 90 km?

Since we have our average speed to be 12km/hr and we have a journey as long as 90km to cover  
Solution
The velocity = 12km/hr
Distance = 90km
Time taken = ?

From our simple velocity equation

V=D/T
Where V = velocity
           D = distance
          T = time taken
Using T as the subject of the formula 

T=d/v
Now input the values above into the equation
T=90km/12kmhr-1
Therefore T = 7hrs,30mins (7.5hrs)

To covert to seconds 
7.5*3600 = 27000secs

To convert to minutes 
7.5*60 = 450mins

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