Answer :
An operation is associative if you can group numbers in any way without changing the answer. It doesn't matter how you combine them, the answer will always be the same.
[tex]a + (b + c) = (a + b) + c \\ \\ 19+(11+37) =(19+11)+37 \\\\19+48=30+37\\\\67=67[/tex]
[tex]a + (b + c) = (a + b) + c \\ \\ 19+(11+37) =(19+11)+37 \\\\19+48=30+37\\\\67=67[/tex]
