Select the correct option that will complete the series. (2, 7), (3, 13), (5, 31), ?, (11, 133)
Show answer & explanation
Correct answer: C
Explanation
First numbers are consecutive prime numbers:
2, 3, 5, 7, 11
Now check rule for second number:
2 → 7 = 2² + 3
3 → 13 = 3² + 4
5 → 31 = 5² + 6
11 → 133 = 11² + 12
So missing pair:
First number = 7
Second number = 7² + 8 = 49 + 8 = 57
Hence, the correct answer is option 3.