What will come in place of question mark (?) in the following number series?
2, 5, 11, 23, 44, 77, ?

`. Let's write out the clean answer and solution XML carefully. Clean answer: 125 (or Option 125 / 125) -> core answer value: "125". Let's double-check formatting requirements: - MathML without LaTeX or entity codes: e.g. `$5-2=3$`. - Raw symbols: `-`, `+`, `=`, `⇒`. - `

` wrapping paragraphs and `$`\; blocks.\; Everything\; is\; clear\; and\; verified.125$

The correct option is 125.

To find the missing number in the series, let's analyze the differences between consecutive terms step-by-step.

Given number series:
2, 5, 11, 23, 44, 77, ?

Step 1: Calculate the first level of differences between consecutive terms

$5-2=3$

$11-5=6$

$23-11=12$

$44-23=21$

$77-44=33$

The first level differences are: 3, 6, 12, 21, 33.

Step 2: Calculate the second level of differences (differences between consecutive first-level differences)

$6-3=3$

$12-6=6$

$21-12=9$

$33-21=12$

The second level differences form a sequence: 3, 6, 9, 12, which increases by 3 each time (multiples of 3).

Step 3: Determine the next terms in the pattern

The next second-level difference will be:

$12+3=15$

Adding 15 to the last first-level difference (33) gives the next first-level difference:

$33+15=48$

Finally, adding 48 to the last term of the series (77) gives the missing number (?):

$77+48=125$

Hence, the number that comes in place of the question mark (?) is 125.