Multiplication order

Hi, First of all, great program! I am not sure if this is intended, but to me the order in which prefixes (n,u,m,k,M,etc) are evaluated is not intuitive. For instance on 1.5.7: ``` > 1k/1M 1000000000 # wrong value, I suppose it is doing (1E3/1)E6 instead of 1E3/1E6 # i would expect this as the right answer, but using the parenthesis is annoying >1k/(1M) 0.001 ```