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put this solution on YOUR website!oct=12 more than sept
sept=x
oct=x+12
nov=twice as much as sept
nov=2x
to find how much they used each month, add them up and equate it to 132
x+x+12+2x=132
4x+12=132
4x=120
x=30
sept=x=30
oct=x+12= 30+12=42
nov=2x=2(30)=60
check:
30+42+60=132