A Boat covers a distance of 30 km downstream in 2 hours while it takes 6 hours to cover the same distance upstream. What is the speed of the boat in kilometre per hour?

Let B and S be the speed of boat and stream respectively

As per the given conditions

30/(B+S)=2

30/(B-B)=6

From eq (i) and (ii):

S=5 ,b= 10 km/hr

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In following questions, a sequence of groups of alphabets and numbers is provided with one term missing , Choose the missing term from options. Q1F, S2E, U6D, W21C, ?

The first letter of each term is moved two steps forward and the last letter is moved one steps backward to obtain the corresponding letters of the next term. The number series runs as follows :

1 x 1 + 1 = 2,

2 x 2 + 2 = 6,

6 x 3 + 3 = 21,

21 x 4 + 4 = 88.

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In following questions, a sequence of groups of alphabets and numbers is provided with one term missing , Choose the missing term from options. J2Z, K4X, 17V, ?, H16R, M22P

The first letters in odd numbered terms from series J, I, H and in even numbered terms from the series K, L, M. The sequence followed by the numbers is + 2, + 3, + 4, + 5, + 6. The third letter of each term is moved two steps backward to obtain the third letter of the next term.

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Excluding stoppages, the speed of train is 50 km per hour and including stoppages it is 40 km per hour. For how many minutes does the train stop per hour?

Due to stopages it is it covers 10 km less.

Time taken to cover 10 km= (10/50)*60 min = 12 min

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A + B means A is the father of B.

A -B means A is the wife of B.

A Ã—B means A is the brother of B.

A Ã·B means A is the daughter of B.

If P Ã·R + S + Q , which of the following is true?

PÃ·R+S+Q means P is the daughter of R who is the father of S who is the father of Q i.e.P is the sister of the father (S) of Q i.e. P is the aunt of Q..

In following questions, a sequence of groups of alphabets and numbers is provided with one term missing , Choose the missing term from options. DEF, HIJ, MNO, ?

The letters in each term are consecutive. There is a gap of one letter between the last letter of the first term and the first letter of the second term and a gap of two letters between the last letter of the second term and the first letter of third term. So, there would be a gap of three letters between the last letter of the third term and the first letter of the fourth term.

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