脫式計算
4800÷25÷4
=4800÷(25x4)
=4800÷100
二48
3.2x0.125x2.5
=0.125x8x(0.4x2.5)
=1x1
=1
9123-(123+8.8)
=9123-123-8.8
=9000-8.8
=8991.2
1.24×8.3+8.3×1.76
=8.3×(1.24+1.76)
=8.3×3
=24.9
61-(1.25+2.5×0.7)
=61-3
=58
解方程:
(1)2x+8=16
2x=16-8
x=8÷2
x=4
(2)x÷5=10
x=5×10
x=50
(3)x+7x=8
8x=8
x=8÷8
x=1
(4)9x-3x=6
6x=6
x=6÷6
(5)6x-8=4
6x=8+4
x=12÷6
x=2
脫式計算
4800÷25÷4
=4800÷(25x4)
=4800÷100
二48
3.2x0.125x2.5
=0.125x8x(0.4x2.5)
=1x1
=1
9123-(123+8.8)
=9123-123-8.8
=9000-8.8
=8991.2
1.24×8.3+8.3×1.76
=8.3×(1.24+1.76)
=8.3×3
=24.9
61-(1.25+2.5×0.7)
=61-3
=58
解方程:
(1)2x+8=16
2x=16-8
x=8÷2
x=4
(2)x÷5=10
x=5×10
x=50
(3)x+7x=8
8x=8
x=8÷8
x=1
(4)9x-3x=6
6x=6
x=6÷6
x=1
(5)6x-8=4
6x=8+4
x=12÷6
x=2