9/5 : 7/4 + 3/4 x 8/7       

= (9/5 : 8/7) x (7/4 + 3/4)

= 63/40 x 5/2

= 63/16

7 x 3/14 - 1/14

= 3/2 - 1/4

= 5/4

_{^{\(\dfrac{9}{5}:\dfrac{7}{4}+\dfrac{3}{4}\times\dfrac{8}{7}\)}}

_{^{\(=\dfrac{9}{5}\times\dfrac{4}{7}+\dfrac{3}{4}\times\dfrac{8}{7}\)}}

_{^{\(=\dfrac{36}{35}+\dfrac{6}{7}\)}}

_{^{\(=\dfrac{66}{35}\)}}

_{^{\(7\times\dfrac{3}{14}-\dfrac{1}{14}\)}}

_{^{\(=\dfrac{3}{2}-\dfrac{1}{14}\)}}

_{^{\(=\dfrac{10}{7}\)}}

\(\frac{9}{14}-\frac{x}{7}:\frac{5}{3}=\frac{3}{14}\Leftrightarrow\frac{9}{14}-\frac{3x}{35}=\frac{3}{14}\Leftrightarrow\frac{3x}{35}=\frac{3}{7}\Leftrightarrow3x=15\Leftrightarrow x=5\)

9/14-x/7:5/3=6/14

x/7:5/3=3/14

x/7=5/14

x=35/7

X = 35 thôi

x/7=2/7

x=2

x/7 * 3/5 =3/7

x/7         =3/7:3/5

x/7          =5/7

x=5

x/7=5/7

x=5

sorry minh nham 

a = 302 / 105

b = 98/9

c= 6/5

tick nha

a=302/105

b 98 /9

c6/5

k nha và học tốt

                   Đề Bài :\(\frac{9}{14}\)- \(\frac{x}{7}\): \(\frac{5}{3}\)= \(\frac{3}{14}\)

ta có : \(\frac{9}{14}\)- \(\frac{x}{7}\)= \(\frac{3}{14}\)x \(\frac{5}{3}\)= \(\frac{5}{14}\)

          \(\frac{x}{7}\)= \(\frac{9}{14}\)- \(\frac{5}{14}\)= \(\frac{4}{14}\)

         \(\frac{4}{14}\)= \(\frac{x}{7}\)=> \(\frac{4}{14}\)= \(\frac{2}{7}\)=> x = 2

9/14 - x/7 : 5/3 = 3/14 

9/14 - x x 1/7 x 3/5 = 3/14

x x 3/35 = 9/14 - 3/14

x x 3/35 = 3/7 

x = 3/7 : 3/35

 x = 5 

vậy x =5

4/5 x 15/11 x 2/9 = 8/33

4/7 x 2/5 + 4/7 x 3/5 = 4/7

( 5/7 + 7/8 ) x 2 =  89/28

2/14 + 3/7 - 3/14 x 2 = 1/7 

tk mình nhé, mk nhanh nhất

4/5 x 15/11 x2/9

= 4x15x2/5x11x9

= 4x5x3x2/5x11x3x3

= 8/33

4/7x2/6+4/7x3/5

=4/7x(2/6+3/5)

=4/7x 14/15

=8/15

y=41/45

8/15

m=33/20

21/22 nhé

6/7

21/35 và 20/35 nhé