In alphabet series, some alphabets are missing which are given in that order as one of the alternatives below it. Choose the correct alternative.

ab _ bc _ c _ ba _ c

The series is abc / bca / cab / abc. Thus, the letters are written in a cyclic order.

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A family consists of six members P, Q, R, X, Y and Z. Q is the son of R but R is not mother of Q. P and R are a married couple. Y is the brother of R. X is the daughter of P. Z is the brother of P. Who is the brother-in-law of R?

Q is the son of R but R is not the mother. So, R is the father of Q. P is married to R. So, P is the wife of R and the mother of Q. X is the daughter of P and hence of R and so she is the sister of Q. Y is the brother of R and Z is the brother of P. R is the husband of P and Z is the brother of P. So, Z is the brother-in-law of R..

In alphabet series, some alphabets are missing which are given in that order as one of the alternatives below it. Choose the correct alternative.

adb _ ac _ da _ cddcb _ dbc _ cbda

The series is adbc acbd abcd dcba dbca cbda.

Thus, the letters equidistant from the beginning and the end of series are the same.

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In following number series, two terms have been put within brackets. Choose the appropriate option

Choose the appropriate option 2, 3, (6), 11, 18, (30), 38

Choose the appropriate option 2, 3, (6), 11, 18, (30), 38

The correct sequence is + 1, + 3, + 5, + 7, + 9, + 11.

Clearly, the term 6 is correct,

But, 30 is wrong and should be replaced by (18 + 9) i.e. 27.

In following questions, one term in number series is incorrect.

Find out the incorrect number 3, 4, 10, 32, 136, 685, 4116

Find out the incorrect number 3, 4, 10, 32, 136, 685, 4116

The sequence is as follows:

2nd term = (1st term + 1) * 1

3rd term = (2nd term + 1) * 2

4th term = (3rd term + 1) * 3 and so on.

So, 32 is wrong and must be replaced by (10 + 1) * 3 i.e. 33..

The difference of the squares of two consecutive odd integers is divisible by which of the following integers ?

Let the two consecutive odd integers be (2n + 1) and (2n + 3). Then,

(2n + 3)2 - (2n + 1)2 = (2n + 3 + 2n + 1) (2n + 3 - 2n - 1)

= (4n + 4) x 2

= 8(n + 1), which is divisible by 8.

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