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2 years ago

A motorboat takes 3 hours to travel 108 kilometers going upstream. The return trip takes 2 hours going

Mathematics

1 answer:

IRISSAK [1]2 years ago

6 0

Answer:

45 km/h and 9 km/h

Step-by-step explanation:

Let the rate of boat in still water be b and the speed of the current be c

Speed downstream = b + c
Speed upstream = b - c

We got equations for time:

108/(b - c) = 3 ⇒ b - c = 36
108/(b + c) = 2 ⇒ b + c = 54

Add up the equations:

b - c + b + c = 36 + 54
2b = 90
b = 45 km/h

Then finding the values of c

c = 45 - 36 = 9 km/h

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