Question

数学题急求！

计算：（-0.8）+（+1.2）+（-0.7）——（-1.2）+0.8
最还有过程

Answer 1

-0.8+1.2-0.7+1.2+0.8 简便运算: -0.8+1.2-0.7+1.2+0.8
=0.4-0.7+1.2+0.8 =1.2+1.2-0.7 (正负0.8对掉）
=-0.3+1.2+0.8 =2.4-0.7
=0.9+0.8 =1.7
=1.7

Answer 2

-0.8+1.2-0.7-1.2+0.8 再简便运算: -0.8+1.2-0.7+1.2+0.8
= 0.4-0.7-1.2+0.8 = 1.2+-（1.2）+0.8+（-0.8）-0.7
= -0.3-1.2+0.8 = 0+0-0.7
= -1.5+0.8 = -0.7
= -0.7

Answer 3

（-0.8）+（+1.2）+（-0.7）+（-1.2）+0.8
=-0.8+1.2-0.7-1.2+0.8
=(-0.8+0.8)+(1.2-1.2)-0.7
=0+0-0.7
=-0.7

Answer 4

解：-0.8+1.2-0.7-1.2+0.8=-0.7

Answer 5

=-0.8+1.2-0.7-1.2+0.8
-0.7