下面各题,怎样算简便就怎样算.3.25+2.36+1.64 &

1个回答

  • 解题思路:(1)根据加法结合律进行计算;

    (2)根据加法交换律进行计算;

    (3)根据减法的性质进行计算;

    (4)先算括号里的,再算括号外面的;

    (5)根据加法交换律和减法的性质进行计算;

    (6)根据减法的性质进行计算.

    (1)3.25+2.36+1.64

    =3.25+(2.36+1.64)

    =3.25+4

    =7.25;

    (2)2.4+4.85-1.4

    =2.4-1.4+4.85

    =1+4.85

    =5.85;

    (3)9.2-2.64-3.14-0.22

    =8.2-(2.64+3.14+2.22)

    =8.2-8

    =0.2;

    (4)13.56-(4.4+3.44)

    =13.56-7.84

    =5.72;

    (5)2.98-3.24+1.12-0.76

    =(2.98+1.12)-(3.24+0.76)

    =4.1-4

    =0.1;

    (6)3.28-(1.2-3.6)

    =3.28-1.2+3.6

    =2.08+3.6

    =5.68.

    点评:

    本题考点: 小数四则混合运算;运算定律与简便运算.

    考点点评: 本题重点考查了学生在小数四则运算中灵活运用简便计算方法来进行计算的能力.