Question

Insert the missing number.7, 26, 63, 124, 215, 342,(....)

• A. 391
• B. 421
• C. 511
• D. 451

Answer 1

The Correct Option is C

Series Pattern and Difference Calculation 

The series follows a pattern where the differences between consecutive numbers increase in a systematic way:

91 - 26 = 65, 19 - 63 = −44, 37 - 124 = −87, 61 - 215 = −154, 91 - 342 = −251, 127 - 342 = −215

The differences are increasing as follows: 19, 37, 61, 91, 127. The next difference should increase by 37, resulting in:

\( 127 + 37 = 164 \)

So, the next number is:

\( 342 + 164 = 511 \)