Missing Number (SSC CGL 2018 Tier-1)

(First number + Third number) = (Total number *2) = (Second number)

19 + 20 = 39 × 2 = 78

25 + 47 = 72 × 2 = 144

16 + 13 = 29 × 2 = 58

Hence, "58" is the correct answer.

(First number - Second number) ² =  (Third  number)

Logic is:- The Difference between the square

12 ^ 2 - 7 ^ 2 = 144 - 49 = 95

14 ^ 2 - 8 ^ 2 = 196 - 64 = 132

16 ^ 2 - 9 ^ 2 = 256 - 81 = 175

Hence, "175" is the correct answer.

9 × 3 = 27 + 1 = 28 ;
28 × 3 = 84 + 1 = 85 .

Similarly...

12 × 3 = 36 + 1 = 37

37 × 3 = 111 + 1 = 112

Hence, "112" is the correct answer.

(1st term + 5) ⇒ (2nd term + 15) = (3rd term)

17 + 5 ⇒ 22 + 15 = 37

23 + 5 ⇒ 28 + 15 = 43

Similarly 16 + 5 ⇒ 21 + 15 = 36

Hence, "21" is the correct answer.

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

6 + 7 = 13

24 + 28 = 52

96 + 112 = 208.

Hence, "208" is the correct answer.

Logic:- In a row addition of the first two, then divided by 9 gives the third number.

50 + 31 = 81/9 = 9

43 + 11 = 54/9 = 6

Similarly, 42 + 21 = 63/9 = 7

Hence, "7" is the correct answer.

Logic:- By going column-wise:

√1st number + 2nd number = Third number.

√9 + 6 = 3 + 6 = 9 ;

√25 + 11 = 5 + 11 = 16

Similarly, √49 + 13 = 7 + 13 = 20

Hence, "20" is the correct answer.

(1st term + 2nd term) ² = 3rd term

4 ^ 2 + 5 ^ 2 = 16 + 25 = 41

6 ^ 2 + 3 ^ 2 = 36 + 9 = 45

7 ^ 2 + x ^ 2 = 49 + x ^ 2 = 58

X ^ 2 = 9 ; x = 3

Hence, "3" is the correct answer.

11 + √16 = 11 + 4 = 15

17 + √36 = 17 + 6 = 23

Similarly, 8 + √4 = 8 + 2 = 10

Hence, "10" is the correct answer.

(1st term - 2nd term) ² = 3rd term

9 ^ 2 - 6 ^ 2 = 81 - 36 = 45

11 ^ 2 - 8 ^ 2 = 121 - 64 = 57

8 ^ 2 - 3 ^ 2 = 64 - 9 = 55

So the missing number is 55.