Is there an official rule covering how combined percentages in SR5 work? Specifically in relation to thinks like essence and product discounts?

There aren't a lot of places where this comes up in the existing core rules yet, but I'm trying to get the spreadsheet I'm working on to be ready for the predictable future rules.

Do two 10% discounts add together to a 20% discount or is it Price x. 9 x. 9 (which is how I think it worked in 4th?)

I expect it to be X .9 X .9 but I wanted to be sure.

I've always been of the assumption that any discount or increase is calculated based on the base price and then they are all applied together at the end to get a final adjusted value.

You mean additive rather than multiplicative, Jack?

I'd imagine it'd mirror SR4. I can't at the moment recall which percentages in 4E were additive, and which were multiplicative, but I'm sure if I fiddled around in Chummer I could figure it out.

~Umi

Yeah, additive. The only thing I can really think of off the top of my head that has this in SR5 is Lifestyle options. So, for instance, if I had a Low Lifestyle and it was both Cramped (-10%) and in a Dangerous Area (-20%), it would cost me 2000 - (2000 * .10) - (2000 * .20) = 1400 With that said, the Lifestyle Options are specifically written as "+/- X% of the lifestyle" if they aren't a straight cost, so it may not be applicable in other situations or contexts.

Toying with Chummer, it looks like Adept Powers are also additive - combining the 25% cost discounts of an Adept Way and a Geas results in an additive 50% discount rather than a 43.75% multiplicative one. (At least in 4E, anyway.)

~Umi

If nobody tells you explicitly to use wrong math, why use it? I mean, you wouldn't calculate all numbers base modulo 5 or something without being told by the rules, right?

Like the song goes, if Logarithming you is wrong, I don't want to be right.......

https://xkcd.com/1162/

I'm a fan of Knuth Paper-Stack Notation.

Heh

Yes.

I would guess that you have the same number of runners combing their hair as in previous editions. Probably upwards of 90%. Sure your mage might like the grunge/bed head look, but the face will likely have proper grooming and the street sam's definitely going to want the hair out of her eyes. It's not like those pink mohawks style themselves after all. Except there seems to be a lot of baldness in the character art, so maybe the sales of Comb Inc. (a wholly owned subsidiary of Hair Tech co. (a wholly owned subsidiary of Ares)) are down this quarter.

*Reads the post and not just the title* . . . oh, nevermind.

Too bad the edit option doesn't let me fix titles.