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


Answer: (c) 17

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


Answer: (d) 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


Answer: (c) 62

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


Answer: (c) 24

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


Answer: (c) 84

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


Answer: (b) 56

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


Answer: (d) 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


Answer: (b) 144

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


Answer: (c) 342

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


Answer: (c) 157

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