Trouble with percentages

Suppose the inflation rate is 10% and increases by 20%.
Does that mean it is 30%?
Or maybe it is 1.1*1.2=1.32 who is a rate of 32%.
Or even 10+20%=10*1.2=12%
My brain acheth.
Actually it is the first one because the second one is for price levels and the third is rubbish.
It would be different if the rate increased by a fifth. Then it would be 12%.