脱式计算.(1)240÷2×5 (2)(111-75)×13 (3)400-128÷4 (4)(45+54)÷3 (5)

1个回答

  • 解题思路:(1)按照从左到右的顺序计算;

    (2)先算小括号里面的减法,再算括号外的乘法;

    (3)先算除法,再算减法;

    (4)先算小括号里面的加法,再算括号外的除法;

    (5)按照从左到右的顺序计算;

    (6)先算乘法,再算减法.

    (1)240÷2×5,

    =120×5,

    =600;

    (2)(111-75)×13,

    =36×13,

    =468;

    (3)400-128÷4,

    =400-32,

    =368;

    (4)(45+54)÷3,

    =99÷3,

    =33;

    (5)25×4×15,

    =100×15,

    =1500;

    (6)1600-85×12,

    =1600-1020,

    =580.

    点评:

    本题考点: 整数四则混合运算.

    考点点评: 本题考查了整数的四则混合运算,关键是理清楚运算的顺序,根据运算顺序逐步求解即可.