Hard
Find the next term in the series: P1B, R3D, T6F, V10H, X15J, ?
Find the next term in the series: P1B, R3D, T6F, V10H, X15J, ?
The first and third letters each advance by 2 (P,R,T,V,X,Z and B,D,F,H,J,L), while the middle number increases by consecutive integers (+2,+3,+4,+5,+6): 1,3,6,10,15,21. Combining these gives Z21L.
Re-check your working by substituting the answer back into the original question.