Answer:
better question Please
80 - [50 - {20/2 - (16 - 2/2) ÷ 3}]
80 - [50 - {20/2 - (15) ÷ 3}]
80 - [50 - {10 - 5}]
80 - [50 - {5}]
80 - [45]
35