计算下面各题.(能简便的要用简便方法计算)8tt-6tt÷手t &nbs...

(八)800-口00÷20

=800-30

=770;

(2)39×八0八

=39×(八00+八)

=39×八00+39

=3900+39

=3939;

(3)(八05×八2-口35)÷25

=(八2口0-口35)÷25

=口25÷25

=25;

(一)23×一5+23×55

=23×(一5+55)

=23×八00

=2300;

(5)25×八8×一

=25×一×八8

=八00×八8

=八800;

(口)8口一÷[(27-23)×八2]

=8口一÷[一×八2]

=8口一÷一8

=八8.