Arithmetic operator confusion

Question

Why I'm getting two different values while using the arithmetic operators for the same value of variables. I've just altered little bit my second program, which is resulted in giving me the different output. Could anyone please tell me why?

    int number=113;
 int rot=0;
 rot=number%10;
 rot*=100+number/10;
 System.out.println(rot);//333



    int number=113;
 int rot=0;
 rot=number%10;
 rot=rot*100+number/10;
 System.out.println(rot);//311

Answer 1

In the first part you compute

rot *= 100 + number/10

which is

rot = rot * (100 + number/10)

And in the second part:

rot = rot*100 + number/10

Note that multiplication and division goes before addition and substraction.