解题思路:①运用除法的性质简算;
②根据乘法结合律简算;
③先算小括号里面的加法,再算括号外的除法;
④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;
⑤⑥可据乘法分配律进行计算即可.
①12.5÷2.5÷0.4
=12.5÷(2.5×0.4)
=12.5÷1
=1.25;
②2.6×1.9÷2.6×1.9
=(2.6÷2.6)×(1.9×1.9)
=1×3.61
=3.61;
③(7.7+1.54)÷0.7
=9.24÷0.7
=13.2;
④10.8÷[(4.62-1.92)×4]
=10.8÷[2.7×4]
=10.8÷10.8
=1;
⑤3.8×6.7+3.3×3.8
=3.8×(6.7+3.3)
=3.8×10
=38;
⑥1.28×0.29-0.29×0.28
=0.29×(1.28-0.28)
=0.29×1
=0.29.
点评:
本题考点: 小数四则混合运算.
考点点评: 考查了运算定律与简便运算,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律简便计算.