Question

Find the missing term in the series:  

\[ X,\ U,\ S,\ P,\ N,\ K,\ \underline{\hspace{1cm}} \]

• A. L
• B. M
• C. J
• D. I

Hint:

When letters are involved, immediately convert them into numerical positions. Alternating difference patterns become much easier to identify.

Answer 1

The Correct Option is D

Concept: In alphabet series questions, it is often useful to convert letters into their corresponding alphabetical positions and then examine the pattern of differences.

Step 1: Convert letters into numerical positions. \[ X=24,\quad U=21,\quad S=19,\quad P=16,\quad N=14,\quad K=11 \] Thus the series becomes \[ 24,\ 21,\ 19,\ 16,\ 14,\ 11 \]

Step 2: Find the successive differences. \[ 24-21=3 \] \[ 21-19=2 \] \[ 19-16=3 \] \[ 16-14=2 \] \[ 14-11=3 \] The pattern is \[ -3,\ -2,\ -3,\ -2,\ -3 \] Hence the next difference should be \[ -2. \]

Step 3: Determine the next term. \[ 11-2=9. \] The \(9^{th}\) letter of the alphabet is \[ I. \] Therefore the missing term is \[ \boxed{I}. \]