用简便方法计算. 36×25 102×24 35×16×125 137×15-15×37.

1个回答

  • 解题思路:(1)把36看作9×4,运用乘法结合律简算;

    (2)把102看作100+2,运用乘法结合律简算;

    (3)把16看作2×8,运用乘法结合律简算;

    (4)运用乘法结合律简算.

    (1)36×25,

    =9×4×25,

    =9×(4×25),

    =9×100,

    =900;

    (2)102×24,

    =(100+2)×24,

    =100×24+2×24,

    =2400+48,

    =2448;

    (3)35×16×125,

    =35×2×8×125,

    =(35×2)×(8×125),

    =70×1000,

    =70000;

    (4)137×15-15×37,

    =15×(137-37),

    =15×100,

    =1500.

    点评:

    本题考点: 运算定律与简便运算;整数四则混合运算.

    考点点评: 完成本题,要注意分析式中数据,运用所学的运算定律,灵活简便.