Problema Solution

Two medical representatives leave a hotel at the same time but travel by car in opposite directions. Rolly's average speed is 3 kph faster than Juancho's. Find their rates of speed if after 5 hours, they are 455 kilometres apart.

Answer provided by our tutors

Let

v = Juancho's rate

v + 3 = Rolly's rate

t = 5 hr the time of the travel

d = 455 km the distance between the cars after 5 houra

Since distance = speed*time and the cars travel in opposite direction we have:

vt + (v + 3)t = d

5v + 5(v + 3) = 455

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click here to see the equation solved for v

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v = 44 kph

v + 3 = 44 + 3 = 47 kph

Juancho's rate was 44 kph while Rolly's rate was 47 kph.