脱式计算,能简算的要简算.17.4÷0.8÷1.25    1.8÷0.2÷0.324÷O.6+0.6÷24    17
1个回答

解题思路:(1)(2)运用除法的性质简算;

(3)先算除法,再算加法;

(4)先算除法和乘法,再算加法.

(1)17.4÷0.8÷1.25,

=17.4÷(0.8×1.25),

=17.4÷1,

=17.4;

(2)1.8÷0.2÷0.3,

=1.8÷(0.2×0.3),

=1.8÷0.06,

=30;

(3)24÷O.6+0.6÷24,

=40+0.025,

=40.025;

(4)17.94÷3.9+5.3×0.4,

=4.6+2.12,

=6.72.

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: 此题考查了小数的四则混合运算,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.