Find the next term in the alpha-numeric series
D4T, F9R, H20P, J43N, ...
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → L 90 L
In a letter-number series, each part of the term follows its own rule, so the first letters, the numbers and the last letters are checked separately.
First letters D, F, H, J: each 2 places ahead in the alphabet, so next comes L
Numbers 4, 9, 20, 43: double and add 1, 2, 3, 4 in turn
\(4\times2+1=9\)
\(9\times2+2=20\)
\(20\times2+3=43\)
\(43\times2+4=90\)
Last letters T, R, P, N: each 2 places back, so next comes L