Find out the wrong number in the given sequence of numbers. 432, 605, 456,…

Concept: In an alternating (interleaved) number series, the terms sitting at odd positions and the terms sitting at even positions each follow their own separate, constant arithmetic pattern (a fixed value added or subtracted every step). To spot the wrong term, split the series into these two sub-sequences and check each one independently for a constant common difference.

1. Separate the series into two sub-sequences: the 1st, 3rd, 5th and 7th terms (432, 456, 480, 504) and the 2nd, 4th, 6th and 8th terms (605, 589, 555, 557).

2. Check the odd-position sub-sequence: 432 + 24 = 456; 456 + 24 = 480; 480 + 24 = 504. Every step matches, so this sub-sequence is consistent throughout.

3. Check the even-position sub-sequence: 605 − 16 = 589, which matches the next term. Continuing the same pattern, 589 − 16 = 573 is expected next, but the term actually given is 555 — a mismatch.

4. Cross-check by working from the other end: the last even-position term is 557, and 573 − 16 = 557, which matches perfectly. This confirms the even-position sub-sequence should read 605, 589, 573, 557 — not 605, 589, 555, 557.

Cross-check: both directions — forward from 589 and backward from 557 — independently point to the same expected value, 573, in place of 555, confirming 555 is the term that breaks the constant-difference pattern.

So, 555 is the wrong number in the given sequence.