Question

{30+[10-5+(-2-3)-18-12}

Answer 1

{ 30 + [ 10 - 5 + ( -2 -3)] -18 -12} = 

{ 30 + [ 10 - 5 + ( -5)] -18 -12} = 

{ 30 + [ 10 - 5 -5] -18 -12} = 

{ 30 + [ 10 - 10] -18 -12} = 

{ 30 + [ 0] -18 -12} = 

{ 30 -18 -12} = 

{ 30 - 30} = 

30 - 30 = 

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