There are two operators of equal priority in
10 * 2 / 4
so they are done in order left to right:
10 * 2 / 4 = 20 / 4 = 5 ------.
Notice that + and - also have equal priority. If they are the only operators in an expression, do the work from left to right.
What is the result of the following?
12 - 2 + 4