calculation return: pre tax vs post tax

you know the r% to cover post tax living expense, there are also inflation i% and fee f% how to calculate pre tax return? is it (1 + r%/(1-t))*(1+i%)*(1+f%)-1 or [(1+r%)*(1+i%)*(1+f%)-1]/(1-t) which is mainly about inflation adj, should it be before or post tax? and fee, before or after tax? why? Thanks

second one is correct. Inflation and fee is after tax only. Since taxes are paid on return.

So is the first one correct based on above explanation?

I actually find some conflict here! In the curriculum it seems regard inflation and manager fee before tax, check v2 p130 case, it definitely apply tax upon both return and inflation. I think it makes sense. but there is a question in 2008 schweser practical volume 1 -2AM-Q6, shows the calculation as the first scenario. can you guys share your opinion please. This is EXTREME important …