问题
解答题
解方程或比例.
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答案
(1)20%x-0.4=7.2,
20%x-0.4+0.4=7.2+0.4,
20%x=7.6,
20%x÷20%=7.6÷20%,
x=38;
(2)
=1.8 x
,0.3 4
0.3x=1.8×4,
0.3x÷0.3=7.2÷0.3,
x=24;
(3)3:8=x:2.4,
8x=3×2.4,
8x÷8=7.2÷8,
x=0.9.
解方程或比例.
|
(1)20%x-0.4=7.2,
20%x-0.4+0.4=7.2+0.4,
20%x=7.6,
20%x÷20%=7.6÷20%,
x=38;
(2)
=1.8 x
,0.3 4
0.3x=1.8×4,
0.3x÷0.3=7.2÷0.3,
x=24;
(3)3:8=x:2.4,
8x=3×2.4,
8x÷8=7.2÷8,
x=0.9.