Question

A boat traveled 125 miles downstream and back. The trip downstream took 5 hours. The trip back took 25 hours. What is the speed of the boat in still water? What is the speed of the current?

Answer 1

Answer:

speed upstream= 5miles/hour

speed downstream=25miles/hour

speed of current=

( speed downstream - speed upstream)/2

(25-5)/2=10miles/hour

Answer 2

Step-by-step explanation:

The speed of boat in still water is 12 miles per hour and speed of current is 9 miles per hour.

Explanation:

As boat travelled 210 miles downstream in 10 hours it's speed is 210/10 = 21 miles per hour.

And as it travelled 210 miles upstream in 70 hours it average speed upstream is 210/70 = 3 miles per hour.

Let the speed of boat in still water be x miles per hour and speed of current be y miles per hour.

As such speed down stream would be

x+y miles per hour and speed down stream would be x−y miles per hour. As such

x+y=21..............(1)

x−y=3................(2)

Adding (1) and (2)

x+y+x−y = 21+3

2x = 24

x = 24/2

x = 12

substitute x=12 in equation (1),

12+y = 21

y = 21−12

y = 9

Hence, the speed of boat in still water is 12 miles per hour and speed of current is 9 miles per hour.