10-10.5÷[5.2×14.6-(9.2×5.2+5.4×3.7-4.6×1.5)]+(1.7+1.9)÷0.225

1个回答

  • 解题思路:本题为典型的小数四则混合运算,据四则混合运算法则计算即可:先算乘除,再算加减,有括号的要先算括号里面的.其中[5.2×14.6-(9.2×5.2+5.4×3.7-4.6×1.5)]能据分配律进行简算.

    10-10.5÷[5.2×14.6-(9.2×5.2+5.4×3.7-4.6×1.5)]+(1.7+1.9)÷0.225×70

    =10-10.5÷[5.2×14.6-9.2×5.2-5.4×3.7+4.6×1.5]+1120,

    =10-10.5÷[(14.6-9.2)×5.2-5.4×3.7+4.6×1.5]+1120,

    =10-10.5÷[5.4×5.2-5.4×3.7+4.6×1.5]+1120,

    =10-10.5÷[(5.2-3.7)×5.4+4.6×1.5]+1120,

    =10-10.5÷[1.5×5.4+4.6×1.5]+1120,

    =10-10.5÷[(5.4+4.6)×1.5]+1120,

    =10-10.5÷[10×1.5]+1120,

    =10-10.5÷15+1120,

    =10-0.7+1120,

    =1129.3.

    点评:

    本题考点: 小数四则混合运算.

    考点点评: 完成本要认真分析式中数据,能用简便方法的要简算.