# Number Series: Exercise-2

#### Overview:

 Questions and Answers Type: MCQ (Multiple Choice Questions). Main Topic: Verbal Reasoning. Verbal Reasoning Sub-topic: Number Series Questions and Answers. Number of Questions: 10 Questions with Solutions.

Directions: What should come in place of the question mark (?) in the following number series?

1. 21, 19, 20, 18, 19, ?

1. 22
2. 19
3. 17
4. 16

Solution: Follow the sequence given below. $$21 \overset{-2}{\longrightarrow}\ 19 \overset{+1}{\longrightarrow}\ 20 \overset{-2}{\longrightarrow}\ 18 \\ \overset{+1}{\longrightarrow}\ 19 \overset{-2}{\longrightarrow}\ \boxed{17}$$

1. 2, 3.5, 5, 6.5, 8, ?

1. 10
2. 10.5
3. 9
4. 9.5

Solution: Add +1.5 with every term, as given below. $$2 \overset{+1.5}{\longrightarrow}\ 3.5 \overset{+1.5}{\longrightarrow}\ 5 \overset{+1.5}{\longrightarrow}\ 6.5 \\ \overset{+1.5}{\longrightarrow}\ 8 \overset{+1.5}{\longrightarrow}\ \boxed{9.5}$$

1. 2, 6, 14, 30, ?

1. 42
2. 52
3. 62
4. 72

Solution: Follow the sequence given below. $$2 \overset{+4}{\longrightarrow}\ 6 \overset{+8}{\longrightarrow}\ 14 \overset{+16}{\longrightarrow}\ 30 \overset{+32}{\longrightarrow}\ \boxed{62}$$

1. 0, 3, 8, 15, ?

1. 20
2. 22
3. 24
4. 25

Solution: Follow the sequence given below. $$0 \overset{+3}{\longrightarrow}\ 3 \overset{+5}{\longrightarrow}\ 8 \overset{+7}{\longrightarrow}\ 15 \overset{+9}{\longrightarrow}\ \boxed{24}$$

1. 4, 12, 24, 40, 60, ?

1. 70
2. 80
3. 84
4. 88

Solution: Follow the sequence given below. $$4 \overset{+8}{\longrightarrow}\ 12 \overset{+12}{\longrightarrow}\ 24 \overset{+16}{\longrightarrow}\ 40 \\ \overset{+20}{\longrightarrow}\ 60 \overset{+24}{\longrightarrow}\ \boxed{84}$$

1. 1, 2, 6, 15, 31, ?

1. 41
2. 56
3. 58
4. 62

Solution: Follow the sequence given below. $$1 \overset{+1^2}{\longrightarrow}\ 2 \overset{+2^2}{\longrightarrow}\ 6 \overset{+3^2}{\longrightarrow}\ 15 \\ \overset{+4^2}{\longrightarrow}\ 31 \overset{+5^2}{\longrightarrow}\ \boxed{56}$$

1. 2, 5, 11, 23, ?

1. 32
2. 38
3. 45
4. 47

Solution: Follow the sequence given below. $$2 \overset{\times 2 +1}{\longrightarrow}\ 5 \overset{\times 2 +1}{\longrightarrow}\ 11 \overset{\times 2 +1}{\longrightarrow}\ 23 \overset{\times 2 +1}{\longrightarrow}\ \boxed{47}$$

1. 198, 194, 185, 169, ?

1. 140
2. 144
3. 152
4. 156

Solution: Follow the sequence given below. $$198 \overset{-2^2}{\longrightarrow}\ 194 \overset{-3^2}{\longrightarrow}\ 185 \overset{-4^2}{\longrightarrow}\ 169 \overset{-5^2}{\longrightarrow}\ \boxed{144}$$

1. 462, 420, 380, ?, 306.

1. 354
2. 348
3. 342
4. 338

Solution: Follow the sequence given below. $$462 \overset{-42}{\longrightarrow}\ 420 \overset{-40}{\longrightarrow}\ 380 \overset{-38}{\longrightarrow}\ \boxed{342} \overset{-36}{\longrightarrow}\ 306$$

1. 2, 7, 17, 37, 77, ?

1. 126
2. 145
3. 157
4. 167

Solution: Follow the sequence given below. $$2 \overset{+5}{\longrightarrow}\ 7 \overset{+10}{\longrightarrow}\ 17 \overset{+20}{\longrightarrow}\ 37 \\ \overset{+40}{\longrightarrow}\ 77 \overset{+80}{\longrightarrow}\ \boxed{157}$$