Here, the terms of the given series are a combination of letters and numerals, which have according to a set pattern.

1)

Find the term which does not fit into the series :

1CV, 5FU, 9IT, 15LS, 17OR


A) 5FU

B) 15LS

C) 9iT

D) 17OR

Answer:

Option B

Explanation:

1st Number : $1+4\rightarrow 5, 5+4\rightarrow 9, 9+4\rightarrow 13, 13+4\rightarrow 17$

2nd letter : $C+3\rightarrow F, F+3\rightarrow I, I+3\rightarrow L, L+3\rightarrow O$

3rd letter : $V-1\rightarrow U, U-1\rightarrow T, T-1\rightarrow S, S-1\rightarrow R$

Thus the term 15LS is wrong andmust be replaced by 13LS

Hence the answer is (b).