we are given
120+[(12÷3)×30)]÷20+100
We can use rule
P: Parenthesis
E: Exponent
M: Multiplication
D: Division
A: Addition
S: Subtraction
so, whichever comes first in this sequence , we will do that operation first
step-1: Firstly, we will solve parenthesis
120+[(12÷3)×30)]÷20+100
(12÷3)=4
120+[4×30]÷20+100
now, we can get rid of another bracket
120+120÷20+100
step-2: Our next operation is division
120+120÷20+100
120÷20=6
120+6+100
step-3: Addition
120+6+100=226
so, we will get
120+[(12÷3)×30)]÷20+100=226...........Answer