You can use BODMAS, it is a acronym that stands for: brackets, orders, division, multiplication, addition, subtraction. This is a general order to see what parts of a equation you solve;
We can see there is a bracket, so we solve that first;
(324-323) = 1
Then numbers next to brackets just means we multiply them, so...
325(1) = 325*1 = 325
Hope this helps! :)