545 - (45+4.25) = 545 - 145 = 400
400/50 - 200/250 + 2^15 : 2^13
= 8 - 80/100 + 2^2
= 8 - 0.8 + 4
= 12 - 0.8 = 11.2
[545-(45+4.25)]:50-200:250+2 mũ 15:2 mũ 13
=[545-(45+100)]:50-200:250+2 mũ 15:2 mũ 13
=[545-145]:50-200:250+2 mũ 15 : 2 mũ 13
=400:50-200:250+2 mũ 15 : 2 mũ 13
=8-0,4+2 mũ 2
=7,6+2 mũ 2
=7,6+4
=11,6