Question

 A motorboat, moving at a speed of 10 km/hour, left a pier traveling against the current of the river. Forty-five minutes after the boat left the pier, the motor of the boat broke, and the boat began drifting with the current. After three hours of drifting with the current, the boat was back at the pier where it had started. What is the speed of the current of the river?

Answer 1

to solve this problem, we must make an set of eqations.first let x be the speed of the current of the waterby using the formula speed x time = distance
the first equation is
(10 - x)0.75 = dand the second equation is
3x = d
equating the equation
(10 - x)0.75 = 3x7.5 - 0.75x = 3x3.75x = 7.5x = 0.2 km/hours is the speed of current