怎样简便怎样计算. 2 9 × 5 11 ×27×33 2 7 ×(1÷ 3 4 - 3 4 ÷1) 2006× 200
1个回答

(1)

2

9 ×

5

11 ×27×33,

=(

2

9 ×27)×(

5

11 ×33),

=6×15,

=90;

(2)

2

7 ×(1÷

3

4 -

3

4 ÷1),

=

2

7 ×(

4

3 -

3

4 ),

=

2

7 ×

7

12 ,

=

1

6 ;

(3)2006×

2004

2005 ,

=(2005+1)×

2004

2005 ,

=2005×

2004

2005 +1×

2004

2005 ,

=2004+

2004

2005 ,

=2004

2004

2005 ,

(4) 3

3

4 ×2.6+ 1

2

5 ×3.75,

=3.75×2.6+1.4×3.75,

=3.75×(2.6+1.4),

=3.75×4,

=15;

(5)

19

43 ×34+53×

19

43 -

19

43 ,

=

19

43 ×(34+53-1),

=

19

43 ×86,

=38;

(6)

5

6 ×

1

10 + 1

1

2 ×0.1+ 2

2

3 ÷10,

=

5

6 ×

1

10 + 1

1

2 ×

1

10 + 2

2

3 ×

1

10 ,

=(

5

6 + 1

1

2 + 2

2

3 )×

1

10 ,

=5×

1

10 ,

=

1

2 .