Let the speed of the boat be x "miles/hour" and the speed of the current be y "miles/hour".
In down stream the trip (x+y) "miles" takes in 1 hour. so, 825 "miles" takes 825/(x + y) "hours".
Hence, as per question
825/(x + y) = 33" "" "(i)
Again, in the trip back, (x - y) "miles" take 1 hour. Hence 825 "miles" take 825/(x - y) "hours".
Hence, as per question
825/(x - y) = 55" "" "(ii)
From equation (i), we get
825/(x + y) = 33
or
x + y = 825/33 = 25" "" "(iii)
From equation (ii), we get
825/(x - y) = 55
or
x - y = 825/55 = 15" "" "(iv)
Now, solving equations (iii) and (iv), we get
x = 20 and y = 5
Hence, the speed of the boat is "20 miles/hours" and the speed of the current is "5 miles/hours".