递等式计算(能简算的要简算). 4.1+3.41-1.41 7.63-(2.1+0.63) 5.1+0.9-5.1+0.9 21-(0.05+13.85)+2.23.

问题描述:

递等式计算(能简算的要简算).
4.1+3.41-1.41    
7.63-(2.1+0.63)
5.1+0.9-5.1+0.9  
21-(0.05+13.85)+2.23.

(1)4.1+3.41-1.41
=4.1+(3.41-1.41)
=4.1+2
=6.1;
(2)7.63-(2.1+0.63)
=7.63-0.63-2.1
=7-2.1
=4.9;
(3)5.1+0.9-5.1+0.9
=(5.1-5.1)+(0.9+0.9)
=0+1.8
=1.8;
(4)21-(0.05+13.85)+2.23
=21-13.9+2.23
=7.1+2.23
=9.33.