The sequence follows a pattern where each term is obtained by multiplying the previous term by an increasing factor. The operations are: divide by 2 (20/2 = 10), multiply by 1 (10*1 = 10), multiply by 1.5 (10*1.5 = 15), multiply by 2 (15*2 = 30), multiply by 2.5 (30*2.5 = 75). Following this pattern, the next step is to multiply by 3 (75*3 = 225).