`18/27-8/27`

`=10/27`

`4/7xx2/5`

`=8/35`

`3/4:2/7`

`=3/4xx7/2`

`=21/8`

\(A=\frac{2^{30}.5^7+2^{13}.5^{27}}{2^{27}.5^7+2^{10}.5^{27}}\)

\(=\frac{2^3\left(2^{27}.5^7+2^{10}.5^{27}\right)}{2^{27}.5^7+2^{10}.5^{27}}\)

\(=2^3=8\)

\(\frac{2^{30}.5^7+2^{13}.5^{27}}{2^{27}.5^7+2^{10}.5^{27}}+\frac{2^{13}.5^7\left(2^{17}+5^{20}\right)}{2^{10}.5^7\left(2^{17}+5^{20}\right)}=2^3=8\)

2: \(=\dfrac{-2}{75}+\dfrac{5}{39}=\dfrac{33}{325}\)

3: \(=\dfrac{6}{11}\left(\dfrac{4}{9}+\dfrac{5}{9}\right)=\dfrac{6}{11}\)

4: \(=\dfrac{7}{19}\left(\dfrac{5}{13}+\dfrac{8}{13}-1\right)=-2\cdot\dfrac{7}{19}=-\dfrac{14}{19}\)

5: \(=\dfrac{2}{7}\left(\dfrac{4}{23}-\dfrac{27}{23}+1\right)=0\)

6: \(=\dfrac{3}{8}\left(\dfrac{3}{7}+\dfrac{4}{7}\right)+\dfrac{11}{8}=\dfrac{3}{8}+\dfrac{11}{8}=\dfrac{14}{8}=\dfrac{7}{4}\)

2/3 x 4/5 + 4/5 x 8/3 = 4/5 x (2/3 + 8/3) = 4/5 x 10/3 = 8/3

27/32 x 16/9 -27/32 x7/9 + 27/32 

= 27/32 x (16/9 - 7/9 + 1 )

=27/32 x 2 

=27/16

\(\frac{2}{3}\) x   \(\frac{4}{5}\) +    \(\frac{4}{5}\) x     \(\frac{8}{3}\)

=\(\frac{4}{5}\) x    ( \(\frac{2}{3}\) +    \(\frac{8}{3}\) )

= \(\frac{4}{5}\) x    \(\frac{10}{3}\)

= \(\frac{40}{15}\) = \(\frac{8}{5}\)

167/77

\(\frac{5}{11}\)x  \(\frac{27}{11}\)-  \(\frac{5}{11}\) x  \(\frac{2}{7}\)

= \(\frac{5}{11}\)x ( \(\frac{27}{11}\)  -  \(\frac{5}{11}\))

=\(\frac{5}{11}\)x \(\frac{22}{11}\)

=\(\frac{5}{11}\) x 2 = \(\frac{10}{11}\)

5/11 x 27/11 - 5/11 x 2/7

= 5/11(27/11 - 2/7)

=5/11 x 167/77

=835/847

=5/11x(27/21-2/7)

=5/11x(9/7-2/7)

=5/11x1

=5/11

\(\frac{5}{11}\cdot\frac{27}{21}-\frac{5}{11}\cdot\frac{2}{7}=\frac{5}{11}\cdot\left(\frac{27}{21}-\frac{2}{7}\right)=\frac{5}{11}\cdot1=\frac{5}{11}\)

5/11 nha