Question

{[(120+2*15):75+4]×12^2-40*5}:80

Answer 1

{[(120+2×15):75+4]×12²-40×5}:80=
={[(120+30):75+4]×12²-40×5}:80=
=[(150:75+4)×144-200]:80=
=[(2+4)×144-200]:80=
=(6×144-200):80=
=(864-200):80=
=664:80=
=8,3

Answer 2

{[(120+2·15):75+4]×12²-40·5}:80 =
{[(120+30):75+4]×12²-40·5}:80 =
[(150:75+4)×12²-40·5]:80 =
[(2+4)×12²-40·5]:80 =
(6×12²-40·5):80 =
(6·144-40·5):80 =
(864-40·5):80 =
664:80 =
8,3