Question

1+2*{3+4*[5+6*(9-7)]}

Answer 1

1+2 x {3 + 4 x [5 +6 x(9-7)]}
=1+2 x [3 +4 x(5 + 6 x 2)]
=1 +2 x (3 + 4 x 17 )
=1 + 2 x( 3 +  68)
=1 +2 x 71 
=1 + 142
143