简算题10.2+9.9+9.5+10.8+10.4+9.7急需(今晚).要的是过程.

问题描述:

简算题10.2+9.9+9.5+10.8+10.4+9.7
急需(今晚).要的是过程.

10.2+9.9+9.5+10.8+10.4+9.7
=(10+0.2)+(10-0.1)+(10-0.5)+(10+0.8)+(10+0.4)+(10-0.3)
=10*6+(0.2-0.1-0.5+0.8+0.4-0.3)
=60+0.5
=60.5

10+10+10+10+10+10+0.2-0.1-0.5+0.8+0.4-0.3
=60+0.5
=60.5

10*6+0.2-0.1-0.5+0.8+0.4-0.3=60.5

10.2+9.9+9.5+10.8+10.4+9.7
=10+0.2+10-0.1+10-0.5+10+0.8+10+0.4+10-0.3
=6*10+0.2+0.8+0.4-0.1-0.5-0.3
=60+1.4-0.9
=60+0.5
=60.5