Question

What should come in place of the question mark (?) in the given series? 1, 2, 5, 12, 2, 58, 121

• A. 20
• B. 25
• C. 24
• D. 27

Answer 1

Answer:

D. 27

Look at the pattern carefully:

Series:
1, 2, 5, 12, ?, 58, 121

Check a pattern:
$1 \times 2 + 0 = 2$
$2 \times 2 + 1 = 5$
$5 \times 2 + 2 = 12$
$12 \times 2 + 3 = 27$
$27 \times 2 + 4 = 58$
$58 \times 2 + 5 = 121$

So the pattern is:
$\text{Next term} = (\text{previous term} \times 2) + 0,1,2,3,4,5...$

Missing term:

$12 \times 2 + 3 = 27$
Final Answer: 27