How can knowing associative property help you compute 2x8x2 mentally

Answer 1

4 * 8
or
16 * 2

Answer 2

Definition: The associative property states that you can add or multiply regardless of how the numbers are grouped. By 'grouped' we mean 'how you use parenthesis'. In other words, if you are adding or multiplying it does not matter where you put the parenthesis. Add some parenthesis any where you like!

If you read the definition maybe it will help