Question

A ship traveled 120 km with the current, and then turned around and traveled back, spending 5h and 24 min on its trip. Find the speed of the current if the speed of the ship in still water is 45 km/hour.

Answer 1

1.58 km/hr

Step-by-step explanation:

We will assign the current’s speed as x km/hr;

Remember; distance / speed = time

Therefore;

120 / 45 + x + 120 / 45 – x = 5.4

120 (45 – x ) + 120 (45 + x) = 5.4 (45 + x)(45 - x)

5400 – 120x + 5400 + 120x = (243 + 5.4x)(45 - x)

5400 – 120x + 5400 + 120x = 243 (45 - x) + 5.4 (45 - x)

10800 = 10935 – 243x + 243 – 5.4x

10800 – 10935 - 243 = - 234x – 5.4x

-378 = -239.4 x

x = 1.58 km/hr