The following question, there are three statements I, II and III. Read the question carefully and mark your answer according to which statements(s) is/are sufficient to the answer the question. Find the ratio of speed of Boat in still water to the speed of the current Statement I: here are three points on the bank of the rivers namely A, B and C. Statement II: B is at the same distance to the A as it is from C the man can row from A to B downstream in 3 hours. Statement III: The man rows from A to B and returns back in 9 hours.?

Option 3 : All I, II and III

From statement I and II

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As B is at same distance with A as with C hence let the distance between AB and BC is d meters

Time taken to row boat A to B

⇒ 3 = d/(x + y)

Where x is the speed of Boat in still water and y is the speed of the stream or current

d = 3(x + y)       -----(i)

From statement III:

Time taken to Row boat A to B and return again to A

On putting value of time for downstream rowing into the equation given here in we get,

⇒ 9 = d/(x - y) + d/(x + y)

⇒ 9 = 3 + d/(x - y)

⇒ 9 - 3 = d/(x - y)

⇒ 6 = d/(x - y)

d = 6(x - y)       -----(ii)

On comparing both equation of d we get,

3(x + y) = 6(x - y)

⇒ 3x + 3y = 6x - 6y

⇒ 3y + 6y = 6x - 3x

⇒ 9y = 3x

⇒ y ∶ x = 1 ∶ 3

Hence we need all the three statements here to answer the questions