1. 54.(53-81)+53.(81-54)=54.53-54.81+53.81-53.54
=(54.53-53.54)+(53.81-54.81)
=0+(53-54).81
=-1.81
=-81
2. Thì b > 0
3. [3.(-2)-(-8)].(-7).(-2).(-5)=[-6+8].(-7).[(-2).(-5)]
=2.(-7).10
=-14.10
=-140
4. 85.(35-27)-35.(85-27)=85.35-85.27-35.85+35.27
=(85.35-35.85)+(35.27-85.27)
=0+(35-85).27
= -50.27
=-1350
5. 2^4.25-37.(-4)+128=(2^4).25-(-148)+128
=16.25+148+128
= 400+148+128
=676
6. -3^2.11+64.(7-23)+23.64= 9.11+64.7-64.23+23.64
=(99+448)-(64.23-23.64)
=547-0
=547
7. 6.(-5)^2-171.(-2)-356=6.25-(-342)-356
= 150+342-356
= 492-356
=136