解方程. :=x:48(1+)x=6.250.26×3-0.9x=6%
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解:(1):=x:48,
??????????? x=×48,
??????? x÷=×48,
?????????????x=10;
(2)(1+)x=6.25,
?????????? x=6.25,
???????x÷=6.25÷,
???????????? x=3.75;
(3)0.26×3-0.9x=6%,
??????? 0.78-0.9x=6%,
?? 0.78-0.9x+0.9x=6%+0.9x,
???????????? 0.78=6%+0.9x,
????????? 0.78-6%=6%+0.9x-6%,
???????????? 0.72=0.9x,
??????? 0.72÷0.9=0.9x÷0.9,
??????????????? x=0.8.
解析分析:(1)根据比例的基本性质,把原式转化为x=48×,再根据等式的性质,在方程两边同时除以求解,(2)先化简方程,再根据等式的性质,在方程两边同时除以求解,(3)先化简方程,再根据等式的性质,方程两边加上0.9x,再同时减去6%,然后同时除以0.9求解.
点评:此题考查了解比例和解方程的能力,注意等号对齐.