Using the principle of direct variation, the solution to the problem given are :
Given the Parameters :
Distance = d
Amount of time = t
d α t ; d = kt
We can find k = constant of proportionality = speed of travel ;
d = 10 miles ; t = 2 hours
10 = 2k
k = 10/2
k = 5
Hence, speed = 5 miles per hour
B.) The direct linear variation expression becomes ;
d = 5t
C.) Distance traveled in 3 hours :
t = 3 hours
d = 5t
d = 5(3) = 15 miles
D. Time taken to travel a distance of 20 miles
d = 5t
20 = 5t
t = 20/5
t = 4 hours
Therefore, it will take 4 hours to travel a distance of 20 miles.
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