Question

计算过程，谢谢！

Answer 1

-(4.2+8.4)+5.7+10
=-12.6+5.7+10
=3.1

追答

不懂可以交流 懂请给好评 谢谢。

Answer 2

=1.5-8.4+10
=-6.9+10
=3.1

Answer 3

15.7-12.6=3.1

追答

？

Answer 4

=1.5-18.4=16.9

Answer 5

15.7-12.6

追答

=3.1