Which term will replace the question mark (?) in the following series?
L8, N9, P64, R25, ?
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → T216
In a letter-number series the letters and the numbers follow separate rules, so each part is checked on its own.
Letters L (12), N (14), P (16), R (18): 2 places ahead each time, so the next letter is \(18+2=20\), that is T
Numbers: \(8=2^3\), \(9=3^2\), \(64=4^3\), \(25=5^2\), so the bases go 2, 3, 4, 5 and the powers cube and square in turn
The next base is 6 with a cube: \(6^3=216\)
So the missing term is T216.