Find the term which does not fit into the series:
1CV, 5FU, 9IT, 15LS, 17OR
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → 15LS
Each term has three parts — a number, a first letter and a second letter — and each part follows its own pattern.
Numbers: 1, 5, 9, 13, 17 — each is 4 more than the one before.
First letters: C, F, I, L, O — each is 3 letters ahead.
Second letters: V, U, T, S, R — each is 1 letter back.
The letters of every term fit, but the fourth number should be \(9+4=13\), not 15. So 15LS does not fit; the correct term is 13LS.