求简便运算要有过程，谢谢！急

1.135+3.346+5.557+7.768+9.979=？

9.8+99.8+999.8+9999.8+99999.8=?

6.11+9.22+8.33+7.44+5.55+4.56+3.67+2.78+1.89=?

1.996+19.97+199.8=?

1.1+3.3+5.5+7.7+9.9+11.11+13.13+15.15+17.17+19.19=?

一、

1.135+3.346+5.557+7.768+9.979

=1.135+9.979+3.346+7.768+5.557

=11.114+11.114+5.557

=27.785

二、

9.8+99.8+999.8+9999.8+99999.8

=5*9.8+(90+900+9000+90000)

=49+99990

=39+100000

=100039

三、

6.11+9.22+8.33+7.44+5.55+4.56+3.67+2.78+1.89

=(6.11+1.89)+(9.22+2.78)+(8.33+3.67)+(7.44+4.56)+5.55

=8+12+12+12+5.55

=44+5.55

=49.55

四、

1.996+19.97+199.8

=(2-0.004)+(20-0.03)+(200-.0.2)

=222-(0.004+0.03+0.2)

=222-0.234

=221.786

五、

1.1+3.3+5.5+7.7+9.9+11.11+13.13+15.15+17.17+19.19

=(1.1+9.9)+(3.3+7.7)+5.5+(11.11+19.19)+(13.13+17.17)+15.15

=11+11+5.5+30.3+30.3+15.15

=27.5+75.75

=103.25