return on margin with commissions return, purchase, anything, commission, buying

simeezee

What am I missing here? Re: calculating return when buying on margin...

V5 p.29 shows count sale commission in numerator and purchase commission in denominator but EOC answer shows count both in numerator and purchase in denominator
like this...
(both (purchase and sale) commissions subtracted in numerator/purchase commission added to cost in denominator)

isn't this double counting?

can't find anything in errata...can anyone clarify this for me please?