Which term will replace the question mark (?) in the alphanumeric series given below?
B1, E2, H6, K21, ?, Q445
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → N88
The letters B, E, H, K advance by three each time, so the missing letter is N, and the series ends with Q as it should.
The numbers follow “multiply by n and add n”: 1 × 1 + 1 = 2, 2 × 2 + 2 = 6, 6 × 3 + 3 = 21, 21 × 4 + 4 = 88, and 88 × 5 + 5 = 445, which matches the last term. The missing term is N88.