It takes a ferryboat 2 hours to travel 30 miles going downstream and 3 hours for the return trip upstream. Wha?

Question

It takes a ferryboat 2 hours to travel 30 miles going downstream and 3 hours for the return trip upstream. What is the ferryboat speed in still water?

Answer 1

Let the speed of boat in still waters be x mph and speed of stream be y mph



UPSTREAM

-------------------



Speed = Distance / Time



( x- y ) = 30 /3 = 10



x- y = 10 ...........(A)



DOWNSTREAM

------------------------



Speed = Distance / Time



x + y = 30 /2 = 15



x + y = 15 .........(B)



(A) + (B)



2x = 25



x = 12.5 mph ANSWER



y = 2.5 mph



CHECK



30 / (12.5+2.5) = 2 hours



30 / ( 12.5-2.5) = 3 hours

Answer 2

remember this rule from someplace? velocity = Distance / Time. S = sixteen / 2 S = 8 mph on the way forward. velocity = Distance / Time. S = sixteen / 8 S = 2 mph on the some time past. the fee of the boat on the some time past is two mph. So via fact the question calls for the fee on the nonetheless water. It potential the version between downstream and upstream. that's basically 6 mph.

Answer 3

30/2 = 15mph

30/3 = 10mph



25mph/2 = 12.5mph