\(\frac{167}{99}\)

\(27+\left(43+11\right)-43-\left(27+11\right)\)

\(=27+43+11-43-27-11\)

\(=\left(27-27\right)+\left(43-43\right)+\left(11-11\right)\)

\(=0+0+0\)

\(=0\)

27+(43+11)-43-(27+11)

= 27 + 43 + 11 - 43 - 27 -11

= ( 27 - 27 ) + ( 43 - 43 ) + ( 11-11 )

= 0 + 0 + 0

=0

\(\frac{\left(\frac{5}{8}+\frac{5}{27}-\frac{5}{49}\right)\cdot8\cdot27\cdot49}{\left(\frac{11}{8}+\frac{11}{27}-\frac{11}{49}\right)\cdot8\cdot27\cdot49}+\frac{6}{11}\)

\(=\frac{8+27-49}{8+27-49}+\frac{6}{11}\)

\(=1+\frac{6}{11}\)

\(=\frac{11}{11}+\frac{6}{11}=\frac{17}{11}\)

\(\frac{\frac{5}{8}+\frac{5}{27}-\frac{5}{49}}{\frac{11}{8}+\frac{11}{27}-\frac{11}{49}}+\frac{6}{11}\)

\(=\frac{5\left(\frac{1}{8}+\frac{1}{27}-\frac{1}{49}\right)}{11\left(\frac{1}{8}+\frac{1}{27}-\frac{1}{49}\right)}+\frac{6}{11}\)

\(=\frac{5}{11}+\frac{6}{11}=\frac{11}{11}=1\)

\(a.=\dfrac{2019}{2020}\times\left(\dfrac{4}{11}+\dfrac{5}{11}+\dfrac{2}{11}\right)\\ =\dfrac{2019}{2020}\times1=\dfrac{2019}{2020}\\ b.=\dfrac{25}{27}\times\left(\dfrac{17}{14}-\dfrac{1}{14}-\dfrac{2}{14}\right)\\ =\dfrac{25}{27}\times1=\dfrac{25}{27}\)

Mai tui giải cho hem

Ta có:

\(A=\frac{2}{3.5}+\frac{2}{5.7}+...+\frac{2}{13.15}\)

\(A=\frac{1}{3}-\frac{1}{5}+\frac{1}{5}-\frac{1}{7}+...+\frac{1}{13}-\frac{1}{15}\)

\(A=\frac{1}{3}-\frac{1}{15}=\frac{4}{15}\)

\(B=2.\left(\frac{1}{1.2}+\frac{1}{2.3}+...+\frac{1}{9.10}\right)\)

\(B=2.\left(\frac{1}{1}-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+...+\frac{1}{9}-\frac{1}{10}\right)\)

\(B=2.\left(\frac{1}{1}-\frac{1}{10}\right)=2.\frac{9}{10}\)

\(B=\frac{9}{5}\)

Vũ Minh TuấnBăng Băng 2k6giúp với

\(\left(1+11+21+31+41+27+37+47\right)^{11}-\left(45+27+17\right)^6⋮2\)

mk ghi lại đề nha

\(\dfrac{5}{27}-\dfrac{2}{-27}=\dfrac{5}{27}+\dfrac{2}{27}=\dfrac{7}{27}\)

\(\dfrac{7}{-25}+\dfrac{-8}{25}=\dfrac{\left(-7\right)+\left(-8\right)}{25}=\dfrac{-15}{25}=\dfrac{-3}{5}\)

\(\dfrac{23}{-11}-\dfrac{-3}{-11}=\dfrac{\left(-23\right)-3}{11}=\dfrac{-26}{11}\)

E

( 27 - 11 )  +  ( 20 - 9 - 27 )

= 27 - 11 + 20 - 9 - 27

= (27 - 27) + 20 - (11 + 9)

= 20 - 20 = 0

đáp số =0

=[(-27)+27]+[20+(-9)+(-11)] = 0+ 0=0

=0 nha Tran Thi Xuan