what is the associative property of an operator

Left Associative means we evaluate our expression from left to right

Right Associative means we evaluate our expression from right to left 
We know *, /, and % have same precedence, but as per associativity, answer may change:

For eg: We have expression: 4 * 8 / 2 % 5

Left associative:   (4 * 8) / 2 % 5 ==> (32 / 2) % 5 ==> 16 % 5 ==> 1

Right associative:  4 * 8 /(2 % 5) ==>  4 * ( 8 / 2) ==> 4 * 4 ==> 16