Mk lộn:

5/9/(1/11-5/22)+5/9/(1/15-2/3)

=-5

5/9/(1/11-5/22)+5/9/(1/15-2/3)

=(107+5) /107-8 < (108+6) /108-7

cách làm wa khó hiểu

a. (-2/3+3/7):4/5+(-1/3+4/7):4/5 

= -5/21.5/4+5/21.5/4

= (-5/21+5/21).5/4

= 0.5/4

= 0

b. 5/9 : (1/11-5/22) + 5/9 : (1/15-2/3)

= 5/9 : (-3/22)+5/9:(-3/5)

= 5/9 . (-22/3)+5/9.(-5/3)

= 5/9.(-22/3-5/3)

= 5/9.-9

= -5

a) \(\left(-\frac{2}{3}+\frac{3}{7}\right):\frac{4}{5}+\left(-\frac{1}{3}+\frac{4}{7}\right):\frac{4}{5}\)

\(=\left[\left(-\frac{2}{3}+\frac{3}{7}\right)+\left(-\frac{1}{3}+\frac{4}{7}\right)\right]:\frac{4}{5}\)

\(=\left[\left(-\frac{2}{3}-\frac{1}{3}\right)+\left(\frac{3}{7}+\frac{4}{7}\right)\right]:\frac{4}{5}\)

\(=0:\frac{4}{5}\)

\(=0\)

b) \(\frac{5}{9}\left(\frac{1}{11}-\frac{5}{22}\right)+\frac{5}{9}\left(\frac{1}{15}-\frac{2}{3}\right)\)

\(=\frac{5}{9}\left[\left(\frac{2}{22}-\frac{5}{22}\right)+\left(\frac{1}{15}-\frac{10}{15}\right)\right]\)

\(=\frac{5}{9}\left[-\frac{3}{22}+\left(-\frac{3}{5}\right)\right]\)

\(=\frac{5}{9}\left(-\frac{81}{110}\right)\)

\(=-\frac{9}{22}\)

a) [(-2/3)+3/7+(-1/3)+4/7] : 4/5 =0:4/5=0

b) 5/9 (1/11-5/22+1/15-2/3)=5/9x(-81/110)=-9/22

a) \(\left(6-\frac{2}{3}+\frac{1}{2}\right)-\left(5+\frac{5}{3}-\frac{3}{2}\right)-\left(3-\frac{7}{3}+\frac{5}{2}\right)\)

\(=6-\frac{2}{3}+\frac{1}{2}-5-\frac{5}{3}+\frac{3}{2}-3+\frac{7}{3}-\frac{5}{2}\)

\(=\left(-\frac{2}{3}-\frac{5}{3}+\frac{7}{3}\right)+\left(\frac{1}{2}+\frac{3}{2}-\frac{5}{2}\right)+\left(6-5-3\right)\)

\(=0+2-\frac{5}{2}+\left(-2\right)=\left(2-2\right)-\frac{5}{2}=0-\frac{5}{2}=-\frac{5}{2}\)

\(=\dfrac{5}{9}:\left(\dfrac{1}{15}-\dfrac{2}{3}+\dfrac{1}{11}-\dfrac{5}{22}\right)\)

\(=\dfrac{5}{9}:\dfrac{-81}{110}\)

\(=\dfrac{-5}{9}\cdot\dfrac{110}{81}=\dfrac{-550}{729}\)

BÀI 1

a,  \(5\times\frac{-7}{10}=\frac{-35}{10}=\frac{-7}{2}\)

b,  \(\frac{4}{5}\times\frac{-7}{10}=\frac{-28}{50}=\frac{-14}{25}\)

c,  \(\frac{4}{9}+\frac{4}{3}\times\frac{16}{4}=\frac{4}{9}+\frac{16}{3}=\frac{52}{9}\)

d,  \(\frac{11}{22}-\frac{3}{9}\times\frac{14}{21}=\frac{11}{22}-\frac{2}{9}=\frac{55}{198}=\frac{5}{18}\)  

BÀI 2

\(A=\frac{6}{13}\times\frac{5}{7}+\frac{6}{13}\times\frac{2}{7}+\frac{17}{13}\)

\(A=\frac{30}{91}+\frac{12}{91}+\frac{17}{13}\)

\(A=\frac{30}{91}+\frac{12}{91}+\frac{119}{91}\)

\(A=\frac{161}{91}=\frac{23}{13}\)

\(B=\frac{11}{15}\times\frac{4}{11}+\frac{11}{15}\times\frac{5}{11}+\frac{11}{15}\times\frac{2}{11}\)

\(B=\frac{4}{15}+\frac{1}{3}+\frac{2}{15}\)

\(B=\frac{11}{15}\)

\(C=\left(\frac{19}{64}-\frac{33}{22}+\frac{24}{51}\right)\times\left(\frac{1}{5}-\frac{1}{15}-\frac{2}{15}\right)\)

\(C=\frac{-797}{1088}\times0\)

\(C=0\)

\(D=\frac{8}{13}\times\frac{7}{12}+\frac{8}{13}\times\frac{5}{12}-\frac{1}{12}\)

\(D=\frac{14}{39}+\frac{10}{39}-\frac{1}{12}\)

\(D=\frac{83}{156}\)

bạn biết câu náy không (24 + 11) . {546 - [14 . (64 - 2^{3}3) : 2]} =

\(\frac{5}{9}:\left(\frac{1}{11}-\frac{5}{22}\right)+\frac{5}{9}:\left(\frac{1}{15}-\frac{2}{3}\right)=\frac{5}{9}:-\frac{3}{22}+\frac{5}{9}:-\frac{3}{5}=-\frac{110}{27}+-\frac{25}{27}=-5\)

5/9 : (2/22 -5/22) + 5/9 : (1/15 -10/15)

=5/9 : -3/22+5/9: -3/5

= -110/27+ -25/27

=   -5

\(\frac{5}{9}:\frac{-3}{22}+\frac{5}{9}:\frac{-3}{5}\)

\(=\frac{5}{9}:\left(\frac{-3}{22}+\frac{-3}{5}\right)\)

\(=\frac{5}{9}:\frac{-81}{110}\)

\(=\frac{-550}{729}\)

\(\frac{5}{9}:\left(\frac{1}{11}-\frac{5}{22}\right)+\frac{5}{9}:\left(\frac{1}{15}-\frac{2}{3}\right)\)

\(=\frac{5}{9}:\left(\frac{2}{22}-\frac{5}{22}\right)+\frac{5}{9}:\left(\frac{1}{15}-\frac{10}{15}\right)\)

\(=\frac{5}{9}:\frac{-3}{22}+\frac{5}{9}:\frac{-3}{5}\)

\(=\frac{5}{9}:\left(\frac{-3}{22}+\frac{-3}{5}\right)\)

\(=\frac{5}{9}:\frac{-81}{110}\)

\(=\frac{-550}{729}\)

\(\frac{5}{9}:\left(\frac{1}{11}-\frac{5}{22}\right)+\frac{5}{9}:\left(\frac{1}{15}-\frac{2}{3}\right)\)

=\(\frac{5}{9}:\left(\frac{2}{22}-\frac{5}{22}\right)+\frac{5}{9}:\left(\frac{1}{15}-\frac{10}{15}\right)\)

=\(\frac{5}{9}:\frac{-3}{22}+\frac{5}{9}:\frac{-3}{5}\)

=\(\frac{5}{9}.\frac{-22}{3}+\frac{5}{9}.\frac{-5}{3}\)

=\(\frac{5}{9}\left(\frac{-22}{3}+\frac{-5}{3}\right)\)

=\(\frac{5}{9}.\left(-9\right)\)

=\(-5\)