Answer
$3[4+3(6-4)]=30$
Work Step by Step
$3[4+3(6-4)]$
Let's start by performing (inside-out) the operations inside the parentheses:
$3[4+3(6-4)]=3[4+3\cdot2]=...$
Now, evaluate the product inside the brackets and then, the sum that will result, also inside the brackets. Then, finally, evaluate the product to finish the problem:
$...=3[4+6]=3[10]=30$