a) x+x=132 <=> 11x=1320 <=> x=120
b) x-x=147 <=> 7x=1470 <=> x=210
c) x+x+[x+x]=363 <=> x+0.1x+0.1(1.1x)=363 <=> 1.1x+0.11x=363 <=> 1.21x=363 <=> x=300
d) x-x-[x-x]=162 <=> x-0.1x-0.1(x-0.1x) =162 <=> 0.9x-0.09x=162 <=> 0.81x=162 <=> x=200
e) (x-0.2x)+0.1(x-0.2x)=145.2 <=> 0.8x+0.08x=145.2