\(\frac{5}{7}.\frac{12}{11}+\frac{9}{7}.\frac{2}{11}-\frac{5}{7}.\frac{14}{11}\)

\(=\frac{1}{7}.\frac{1}{11}.\left(5.12+9.2-5.14\right)\)

\(=\frac{1}{77}.\left(60+18-70\right)\)

\(=\frac{1}{77}.8=\frac{8}{77}\)

\(\frac{8}{77}\)nghe bn

\(\left(\frac{5}{7}-x\right)\times\frac{14}{5}=\frac{7}{10}+\frac{1}{2}\)

\(\left(\frac{5}{7}-x\right)\times\frac{14}{5}=\frac{6}{5}\)

                   \(\frac{5}{7}-x=\frac{6}{5}:\frac{14}{5}\)

                   \(\frac{5}{7}-x=\frac{3}{7}\)

                              \(x=\frac{5}{7}-\frac{3}{7}\)

                               \(x=\frac{2}{7}\)

x=2/7

bài này lớp 4

mình đã học rồi

cho lên bay giờ mình quen rùi

a) 8/15 + 1 = 23/15

b) 3/14 + 11/14 - 2/3 = 1- 2/3 = 1/3

c) 7/15 * (5/3+2/3) = 7/15 * 7/3= 49/45

d) 6/11 + 5/11 - 3/5 = 1 - 3/5 = 2/5

a=23/18

b=1/3

c=49/4

d=2/5

 6+2+5+7+5

=8+5+7+5

=13+7+5

=20+5

=25

6 + 2 + 5 + 7 + 5 =

= 6 + 2 + 7 + ( 5 + 5 )

=8 + 7 + 10

=15 + 10

= 25

\(\left(\frac{5}{7}-y\right)\cdot\frac{14}{5}=\frac{7}{10}+\frac{1}{2}=\left(\frac{5}{7}-y\right)\cdot\frac{14}{5}=\left(\frac{5}{7}-y\right)\cdot\frac{14}{5}=\frac{6}{5}\)\(\frac{6}{5}\) 

\(=>\frac{5}{7}-y=\frac{6}{5}\) / \(\frac{14}{5}=\frac{5}{7}-y=\frac{3}{7}=\frac{5}{7}-\frac{3}{7}=\frac{2}{7}\) 

\(=>y=\frac{2}{7}\)

\(2005:\frac{5}{2}=\frac{2005}{1}\cdot\frac{2}{5}=802\)

\(5+\frac{2}{3}=\frac{5}{1}+\frac{2}{3}=\frac{15+2}{3}=\frac{17}{3}\)

\(\frac{22}{7}-1=\frac{22}{7}-\frac{7}{7}=\frac{15}{7}\)

\(7\cdot\frac{2}{14}=\frac{7}{1}\cdot\frac{2}{14}=\frac{14}{14}=1\)

\(==\)Chúc bn học tốt

2005:5/2=802

5+2/3=17/3

22/7-1=14/7

7x2/14=1

Chúc bạn học tốt

 ( 5/7 - y ) * 14/5 = 7/10 + 1/2

( 5/7 - y ) x 14/5 = 6/5

 5/7 - y  = 6/5 : 14/5

5/7 - y = 3/7

y = 5/7 - 3/7

y = 2/7

bằng 2/7

(5/7 + 9/7 - 5/7) = 9/7

12/11 + 2/11 - 14/11 =1

9/7 x 1 = 9/7

violympic đúng ko nè bạn

chờ chút để mik giải nhé

\(\left(\frac{5}{7}-y\right).\frac{14}{5}=\frac{7}{10}+\frac{1}{2}\)

\(\left(\frac{5}{7}-y\right).\frac{14}{5}=\frac{6}{5}\)

\(\frac{5}{7}-y=\frac{6}{5}:\frac{14}{5}\)

\(\frac{5}{7}-y=\frac{3}{7}\)

\(y=\frac{5}{7}-\frac{3}{7}\)

\(y=\frac{2}{7}\)