Question about crit chance runes and rounding.

Let's say I have 9 crit marks. That's 8.37

Plus 4 crit seals. That's 1.68

8.37+1.68 = 10.05% (shows as 10%)

But 3 crit seals make the total 9.63% (shows as 9.6%). However, in game, it rounds to 10%

My question is, with 3 crit seals, do I still get 10%? Or is it simply a rounding showing of numbers.

Similarly, is 1 crit mark .93% or treated as 1% ingame?