Missing Number – Railway Reasoning part – 2

Logic :- (Previous No × 2) in each
column = Next Number.
For the first column :
 21 × 2 = 42
 42 × 2 = 84
For the third column :
 9 × 2 = 18
 18 × 2 = 36
So, for the second column :
 18 × 2 = 36
 36 × 2 = 72
i.e. the correct answer is = 36

Logic : The given number are written in the reverse numerical order in pair of 2
Order:- 12, 34, 56, 78, 910, 1112
Reverse order is :- 21, 43, 65, 87, 109, 1211

( 13 + 7 ) ÷ 5 = 4
( 13 + 7 ) ÷ 4 = 5
( x + 9 ) ÷ 3 = 6 ⇒ x = 9

2³ = 8
1³ = 1
3³ = 27
So that 4³ = 64

Logic :- Square of consecutive numbers in descending order.

Logic : In triangle corners,
1st number square = 2nd number , 2nd number square = 3rd number

Logic: The letter in the middle is the sum of the opposite letters.
Y + A = Z
E + U = Z
J + P = Z

Logic :
6 × 2 = 12 ⇒ 12² = 144
5 × 3 = 15 ⇒ 15² = 225
3 × 2 = 6 ⇒ 6² = 36
4 × 4 = 16 ⇒ 16² = 256

1² + 2² + 3² + 5² = 39
2² + 3² + 4² + 5² = 54
1² + 3² + 4² + 5² = 1 + 9 + 16 + 25 = 51

Logic : (Taking first term as 2) × (second term) = Middle term
So, according to the logic option ‘c’ follows.
2 × 10 = 20