`a: =(7/3-4/3)+11/5=16/5`

`b: =(18/13-5/13)+55/46=1+55/46=101/46`

`c: =27/25-4/9-2/25+5/9=(27/25-2/25)+(5/9-4/9)=1+1/9=10/9`

Hxjdksks

\(\dfrac{5}{3}\times\dfrac{3}{17}+\dfrac{3}{17}\times\dfrac{1}{3}-\dfrac{3}{17}\times2\)

\(=\dfrac{3}{17}\times\left(\dfrac{5}{3}+\dfrac{1}{3}+2\right)=\dfrac{3}{17}\times4=\dfrac{12}{17}\)

a)  ( − 125 ) . ( − 5 ) .8. ( − 2 ) = ( − 125 ) .8. ( − 5 ) . ( − 2 ) = − 1000.10 = − 10000

b)  ( − 127 ) . ( 1 − 582 ) − 582.127 = ( − 127 ) . ( − 581 ) − 582.127 = 127.581 − 582.127 = 127 ( 581 − 582 ) = 127. ( − 1 ) = − 127

c)  ( 43 − 13 ) . ( − 3 ) + 27. ( − 14 − 16 ) = 30. ( − 3 ) + 27. ( − 30 ) = ( − 30 ) .3 + 27. ( − 30 ) = ( − 30 ) . ( 3 + 27 ) = ( − 30 ) .30 = − 90

d)  125. ( − 61 ) . ( − 2 ) 3 . ( − 1 ) 2 n = 125. ( − 62 ) . ( − 8 ) .1 = 125. ( − 8 ) . ( − 62 ) = − 1000. ( − 62 ) = 62000

1 1/3 x 1 1/4 x 1 1/5 x 1 1/6 x 1 1/7 x 1 1/8 = 4/3 x 5/4 x 6/5 x 7/6 x 8/7 x 9/8 = 4x5x6x7x8x9/3x4x5x6x7x8 = 9/3 = 3

a/ 4/5x3/7+4/7x4/5

=4/5x(3/7+4/7)

=4/5x1=4/5

B/ ta có : 4/3=24/18

               5/3=30/18

=> các phân số cần điền:24/18;25/18;26/18;27/18;28/18;29/18

a

4/5x3/7+4/7x4/5

=4/5x(3/7+4/7)

=4/5x1

=4/5

b)

tui chưa biết làm

Bài 2:

Sau 2 giờ con ốc sên bò được:

1/5+1/6=11/30(cây cột)

Sau 2 giờ thì con ốc sên còn phải bò:

1-11/30=19/30(cây cột)

a)2006x(2004-1004)

=2006x1000

=2006000

a)2006x(2004-1004)

 =2006x1000

 =2006000

b)=15/10+1

   =25/10

   =5/2