# Find the missing number

Find the missing number in the following sequences:

**1)** 61, 52, 63, 94, __ , 18, 001, 121

*[CSIR NET, June, 2014, Mathematical Sciences.]*

A) 46 B) 70 C) 64 D) 44

**2)** 4, 2, 6, 8, 14, __ , 36

A) 16 B) 12 C) 22 D) 30

**3)** 72, 46, __ , 612, 343

A) 105 B) 521 C) 703 D) 13

**4)** 1, 3, 6, 8, 16, 18, 36, __ , 76

A) 74 B) 72 C) 38 D) 42

**5)** 1, 2, 4, 7, 11, __ , 22

A) 16 B) 18 C) 17 D) 12

**6)** 3, 5, 7, 11, __ , 17

A) 17 B) 14 C) 15 D) 13

**7)** 1, 6, 16, 31, __ , 76, 106

A) 61 B) 51 C) 36 D) 32

**8)** 2, 6, 12, 20, 30, __ , 56

A) 44 B) 36 C) 42 D) 48

**9)** 1, 3, 7, 2, 6, 10, 3, __ , 13

A) 11 B) 9 C) 7 D) 5

**10)** 1, 1, 3, 15, __ 945

A) 25 B) 95 C) 75 D) 105

_______________________________________________________

**Answers:**

**1)** A) [Hint:- 61, 52, 63, 94, __ , 18, 001, 121 -> 16, 25, 36, 49, __ , 81, 100, 121.]

**2)** C) [Hint:- 4+2=6, 2+6=8 etc.]

**3)** B) [Hint:- 72, 46, __ , 612, 343 -> 27, 64, __ , 216, 343]

**4)** C) [Hint:- 1+2=3, 3×2=6, 6+2=8, 8×2=16 etc.]

**5)** A) [Hint:- 1+1=2, 2+2=4, 4+3=7, 7+4=11 etc.]

**6)** D) [Hint:- Odd prime numbers in order.]

**7)** B) [Hint:- The difference between two consecutive terms are increased by 5.]

**8)** C) [Hint:- Multiplication of two consecutive natural numbers.]

**9)** B) [Hint:- 1, 3, 7, 2, 6, 10, 3, __ , 13 -> 1,2,3 ; 3,6, __ ; 7,10,13]

**10)** D) [Hint:- 1×1=1, 1×3=3, 3×5=15, 15×7=105, 105×9=945]