Ten important Questions of Reasoning series completion for competitive exams

Formula:- 

Any Term = n² × (n-1), where 'n' is natural number less than equal to 6

1st Term = 1² × (0) = 1 × 0 = 0

2nd Term = 2² × (1) = 4 × 1 = 4

3rd Term = 3² × (2) = 9 × 2 = 18

4th Term = 4² × (3) = 16 × 3 = 48

5th Term = 5² × (4) = 25 × 4 = 100

6th Term = 6² × (5) = 36 × 5 = 180

Hence Option (4)100 is correct.

Formula:-

Any Term =  Previous Term + ( sum of digits of Previous Term)

1st Term =17

2nd Term =17 + (1+7) = 17+ 8 = 25
3rd Term = 25 + (2+5) = 25 + 7 = 32

4th Term =32 + (3+2) = 32 + 5 = 37

5th Term =37 + (3+7) = 37+ 10 = 47

6th Term =47 + (4+7) = 47+ 11 = 58 = Question mark

Hence Option (2)58 is correct.

Formula:-

Difference of any two  consecutive terms = 4 +  Difference of next two consecutive terms

Difference of 2nd term and 1st term = 7 - 5 = 2
Difference of 3rd term and 2nd term = 13 - 7 = 6

Difference of 4th term and 3rd term = 23 - 13 = 10

Difference of 5th term and 4th term = 37 - 23 = 14

Difference of 6th term and 5th term = 55 - 37 = 18

Difference of 7th term and 6th term = ? - 55 = must be 4 greater than previous difference i.e. 18 + 4 = 22

? - 55 = 22

? = 22 + 55

? = 77
Hence Option (3)77 is correct.

1st term = 0.15 × 2 = 0.30 = 0.3

2nd  Term = 0.3 × 2 =  0.60 = 0.6

Also 5th Term =  1.2  × 2 = 2.4

Similarly 3rd =  0.3  × 2 = 0.6= 0.60

4th Term = 0.6 × 2 = 1.2

5th Term = 1.2 × 2 = 2.4 

Hence Option (1)0.6 is correct.

3rd term = 1 + 1 = 2

4th Term = 1 + 2 = 3

5thTerm = 2 + 3 = 5

6thTerm = 3 + 5 = 8

7th Term = 5 + 8 = 13

8th Term = 8 + 13 = 21

missing Term = 13 + 21 = ?

                           ? = 34

Hence Option 12)34 is correct.

Formula:-

Any Term = Square of Previous Term + 1

1st Term = 3

2nd  Term = (1st Term)² + 1

2nd Term =3² + 1 = 9 + 1 = 10

3rd  Term = (2nd Term)² + 1

3rd Term = 10² + 1 = 100 + 1 = 101

4th  Term = (3rd Term)² + 1

4th Term = 101² + 1 = 10201 + 1 = 10202 = The value of question mark

3² +1 , 10² + 1 , 101² + 1

Hence Option (1)19202 is correct.

Formula:-

Any Term = Twice of Previous Term + Rank of previous term

1st Term = 13

2nd Term = (13 × 2) + 1

3rd Term = (27 × 2) + 2

4th Term = (56 × 2) + 3

5th Term = (115 × 2) + 4 = 230 + 4 = 234

Hence Option (4)234 s correct.

Formula:-

Any Term = Four times of Previous Term - 1

2nd  Term = (2 × 4) - 1 = 7

3rd Term = (7 × 4) - 1 = 27

4th Term = (27 × 4) - 1 = 107

                = (107 × 4) - 1 

                = 428 - 1 = 427 

Hence Option (2)427 s correct.

Formula:-

Any Term = Twice of Previous Term  1 

2nd  Term = (2 × 2) + 1 = 4 + 1 = 5

3rd Term = (5 × 2) - 1 = 10 - 1 = 9

4th Term = (9 × 2) + 1 = 18 + 1 = 19

(19 × 2) - 1 = 38 - 1 = 37

(37 × 2) + 1 = 74 + 1 = 75

Hence Option (2)75 s correct.