Đáp án:
a) (39.42-37.42)÷42
=(42.(39+37))÷42
=(42.76)÷42
=3192÷42=76
b)136.68+16.272
=9248+4352=13600
c) 28.(231+69)+72(131.169)
=28.300+72.300
=300.(28+72)
=300.100=30000
d) (27.45+27.55)÷(2+4+6+...+16+18)
=(27.(45+55)÷((18-2)÷2=1)
=(27.100)÷9
=2700÷9=300
e) 2³.15-(115-(12-5)²)
=8.15-(115-7²)
=120-(115-49)
=120-66=54
i) 36.333-108.111
=11988-11988=0
g) 800.(50.(18-2³)÷2+3²))
=800.(50.(18-8)÷2+9))
=800.(50.10÷2+9)
=800.(500÷2+9)
=800.(250+9)
=800.250=207200
h) 100÷(250÷(450-(4.5³-2³.25))
=100÷(250÷(450-(4.125-8.25))
=100÷(250÷(450-(500-100)
=100÷(250÷(450-400)
=100÷(250÷50)
=100÷5=20
CHÚC BẠ HỌC TỐT NHA!!!
