用简便方法计算.4.35+8.6+15.65+1.4 19.32-5.56-3.44 37.6-(7.6+3.25) 5
1个回答

解题思路:(1)(6)可根据加法交换律及结合律计算;

(2)可根据一个数减两个数,等于用这个数减去这两个数的和的减法性质计算;

(3)可根据一个数减两个数的和,等于用这个数分别减去这两个数的减法性质计算;

(4)(5)可根据加法交换律计算.

(1)4.35+8.6+15.65+1.4

=(4.35+15.65)+(8.6+1.4),

=20+10,

=30;

(2)19.32-5.56-3.44

=19.32-(5.56+3.44),

=19.32-9,

=10.32;

(3)37.6-(7.6+3.25)

=37.6-7.6-3.25,

=30-3.25,

=26.75;

(4)5.49+2.68-3.49

=5.49-3.49+2.68,

=2+2.68,

=4.68;

(5)6.27+3.83+1.73

=6.27+1.73+3.83,

=8+3.83,

=11.83;

(6)8.4+3.5-8.4+3.5

=8.4-8.4+(3.5+3.5),

=0+7,

=7.

点评:

本题考点: 运算定律与简便运算;小数的加法和减法.

考点点评: 本题考查了学生运用运算定律完成小数加减法题目的能力.