计算下面各题,怎样算简便就怎样算.
1个回答

(1)15×

3

8 ÷

9

4

=15×

3

8 ×

4

9

=2

1

2 ;

(2)30×(

2

5 +

1

6 -

4

15 )

=30×

2

5 +30×

1

6 -30×

4

15

=12+5-8

=9;

(3)

2

5 ×

7

13 +40%×

6

13

=

2

5 ×

7

13 +

2

5 ×

6

13

=

2

5 ×(

7

13 +

6

13 )

=

2

5 ×1

=

2

5 ;

(4)10-(

2

5 +

3

5 ×2)

=10-(

2

5 +

6

5 )

=10-1

3

5

=8

2

5 ;

(5)

7

15 +

1

4 ×

12

5 -

3

5

=

7

15 +

3

5 -

3

5

=

7

15 ;

(6)[(

7

5 -1)÷

2

5 ]×

5

4

=[

2

5 ÷

2

5 ]×

5

4

=1×

5

4

=1

1

4 .