下面各题怎样算简便就怎样算.
18.65-3.7+1.35-6.330×[3.61÷(7.2-5.3)]36÷[1.44×(0.1-0.05)](16.5×3+3×7.5)÷6.
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解:(1)18.65-3.7+1.35-6.3,
=(18.65+1.35)-(3.7+6.3),
=20-10,
=10;
(2)30×[3.61÷(7.2-5.3)],
=30×[3.61÷1.9],
=30×1.9,
=57;
(3)36÷[1.44×(0.1-0.05)],
=36÷[1.44×0.05],
=36÷0.072,
=500;
(4)(16.5×3+3×7.5)÷6,
=[(16.5+7.5)×3]÷6,
=[24×3]÷6,
=72÷6,
=12.
解析分析:(1)根据加法结合律和减法的性质简算;
(2)先算小括号里面的减法,再算中括号里面的除法,最后算括号外的乘法;
(3)先算小括号里面的减法,再算中括号里面的乘法,最后算括号外的除法;
(4)先把小括号里面的计算运用乘法分配律简算,再算括号外的除法.
点评:本题考查了四则混合运算,注意运算顺序和运算法则,灵活运用所学的运算定律进行简便计算.