问题 计算题
下面各题怎样简便就怎样算。                    
(1)3.8+1.94+0.2+1.06 (2)31.65-7.64-8.36
(3)15.18-9.99+1.82(4)8.7+3.92-5.92
(5)17.85+3.74-5.56(6)45.6-(83.7-78.8)
答案

 

(1)3.8+1.94+0.2+1.06 
        =(3.8+0.2)+(1.94+1.06)
        =4+3
        =7(2)31.65-7.64-8.36
        =31.65-(7.64+8.36)
        =31.65-16
        =15.65
(3)15.18-9.99+1.82
        =15.18+1.82-9.99
        =17-9.99
        =7.01  (4)8.7+3.92-5.92

        =8.7-(5.92-3.92)

        =8.7-2

        =6.7

(5)17.85+3.74-5.56

        =21.59-5.56

        =16.03 (6)45.6-(83.7-78.8)

        =45.6-4.9

        =40.7

单项选择题
单项选择题