that's why i'm asking,is that dot means "divided by two times"?

coz last i know,it just simply means "times" or multiply...

BODMAS says division first so it's 24 multiplied by 12 which is 288

if that's the case then...

48/12=4...

or i'm wrong,that thing means half then multiply...

that'll be the only clear idea that makes the answer is 288

Your encoding isn't set to read the elementary division symbol. It reads as:

Forty eights divided by two, open parenthesis nine plus three close parenthesis.

Parentheses - Exponents - Multiplication - Division - Addition - Subtraction

With the priority going from left to right.

By that logic, the problem should go like this:

48÷2(9+3)

48÷2(12) the parenthesis go first, naturally.

48÷24 Next comes multiplication, between the 2 and the 12.

2 Being that there is only one action left, the answer is two.

The trouble with this particular problem is that multiplication and division (like addition and subtraction) are often given the same priority status. The answer you come up with depends on what version of the order of operations your algebra teacher taught you in high school.