How many seams are there in a soccer ball with 12 pentagons?

It is the total number of edges divided by 2. This is because a seam connects to edges. There are a total of 32 shapes on a soccer ball with 12 pentagons. There are 12 pentagons and 20 hexagons. Here are the calculations:

(12*5/2)+(20*6/2)=180/2=90

So there are 90 seams on a soccer ball with 12 pentagons.