Umm Im in 5th grade and I do not under stand this at all because I don't know what the brakets are and how do you you use them heres the question 108 + 3[15 - (3 + 9)]=?
First do the stuff in parentheses.
(3 + 9) = 12
Then, do what's in the brackets.
[15 - 12] = 3
Next, multiply:
3 * 3 = 9
The last step:
108 - 9 = 99