Question

What should come in the place of the question mark (?) in the following alphanumeric series? A1X, B4P, E25J, J100F, ?

• A. O289D
• B. O225E
• C. Q289D
• D. Q225E

Answer 1

The Correct Option is C

Step 1: Break down each term

Term	First Letter	Number	Last Letter
A1X	A	1	X
B4P	B	4	P
E25J	E	25	J
J100F	J	100	F

Step 2: Analyze First Letters (A, B, E, J)

Alphabet positions:

• A = 1
• B = 2 (+1)
• E = 5 (+3)
• J = 10 (+5)

Pattern: Differences increase by 2 (1, 3, 5), so next difference should be +7

Next letter position: 10 + 7 = 17 → Q

Step 3: Analyze Numbers (1, 4, 25, 100)

Sequence inside squares:

• 1 = 1²
• 4 = 2²
• 25 = 5²
• 100 = 10²

Base numbers: 1, 2, 5, 10

Differences: +1, +3, +5 (increasing by 2), so next difference should be +7

Next base number: 10 + 7 = 17 → 17² = 289

Step 4: Analyze Last Letters (X, P, J, F)

Alphabet positions:

• X = 24
• P = 16 (-8)
• J = 10 (-6)
• F = 6 (-4)

Pattern: Differences decrease by 2 (-8, -6, -4), so next difference should be -2

Next letter position: 6 - 2 = 4 → D

Step 5: Combine Components

Next term: Q289D

Step 6: Match with Options

The correct option is (3) Q289D.