How would you react?
 

If you seen a person walking up the street nude?

If it looks they do so of their own free will... I'd watch, maybe snap a pic if they look interesting, and wish I would dare to do this myself.
Otherwise, offer help.

Hey maybe one day you can

This is an old question which tends to spark a lot of debate - most comments at polar opposites

Another version of the question is would your reaction be different if you saw a naked male or a naked female

Overriding answers tend to be that males would be reported to the authorities whereas females would be clothed and nurtured

I had hoped to get a reply like this

So how would you react to both genders?

I would ask to join them

For me it'd be more like, want to make a bet with me? lol

I would be shocked and probably just ignore them. They could be crazy or maybe doing a dare, but I would not know or bother them.

Well at least you'd leave them to it

I suppose it depends on context. If they look dazed or confused they might need help and a spare shirt. If they're walking along confidently though I'd probably look away and mutter something about the desegregation of society.

Think "ok that's a thing..." and continue on my way. Probably try to not look at them because I wouldn't want to make it awkward.

Ha ha well that's one way to react

Well, my first concern would be if there were any children around for starters. After that, if they're aroused (eye candy), and then if there wasn't anything else wrong, I'd let them, or if I was nearby, strike up a conversation.

like other have mentioned, it depends on the situation. If they seem confused or lost, then I'd offer help. If they appear confident and purposeful, then I'd ask what bet/dare they lost, and if they'd pose for some pictures.

i would be surprised and aroused, stare for a min or so then move on