Try this option (it is not the only way): 1. if to use for consecutive odd numbers: n; n+2; n+4 and n+6), then it is possible to write their sum in equation: n+n+2+n+4+n+6=40. 2. if to solve this equation: n=7 it means that 7 - the 1st number of the given sequence. Using n=7 the 2d number of this sequence is n+2=9.
