Are the percentages cumulative?

[Mewtarthio]

Say I build Hollywood (+50% Culture) and a Synagogue (+50% Culture) and my city's culture besides that is a ridiculous 100 cpt. Am I now producing 200 cpt or 225 cpt?

 

[Shillen]

It adds the %'s together then modifies the base value. So, no, it's not compounded.

 

[walkerjks]

Phrased another way, they are additive, and not multiplicative.

 

[narmox]

Multiplicative % are bad anyway: 50% x 50% = 0.5 x 0.5 = 0.25 = 25%

 

[Grunthex]

Actually a 50% bonus would be 150%, which multiplied would be 225%, Narmox.

But to the OP, as the others have said, the game will take (100 CPT + (50% +50%)) = 200 CPT.