Sue has $4, tom has $11, brian has $6, and anita has $9. use mental math to find how much money they have altogether. show your work.

So you want to add together 4, 6, 11, and 9.

So to make it easier, I would first add together 4 and 6, and 11 and 9.

4 and 6 added together is 10

11 and 9 added together is 20

So, just 20 + 10, or 30.