It takes 3*20=<<3*20=60>>60 minutes to clean the living room
So it is 60/60=<<60/60=1>>1 hour
The bathroom takes 1*2=<<1*2=2>>2 hours
So all together the inside takes 1+1+2=<<1+1+2=4>>4 hours
The outside takes 4*2=<<4*2=8>>8 hours
So the chores take 4+8=<<4+8=12>>12 hours
He splits it 1+2=<<1+2=3>>3 ways
So he works 12/3=<<12/3=4>>4 hours
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