Sửa đề : \(-\dfrac{19}{37}=\dfrac{19}{37}\)

\(\dfrac{19}{37}-\dfrac{31}{24}-\dfrac{19}{37}+1\dfrac{7}{24}-\dfrac{2}{13}\)

\(=\dfrac{19}{37}-\dfrac{31}{24}+\dfrac{19}{37}+\dfrac{31}{24}-\dfrac{2}{13}\)

\(=\left(\dfrac{19}{37}-\dfrac{19}{37}\right)+\left(-\dfrac{31}{24}+\dfrac{31}{24}\right)-\dfrac{2}{13}=-\dfrac{2}{13}\)

Sửa đề: \(\dfrac{19}{37}-\dfrac{31}{24}+\dfrac{-19}{37}+1\dfrac{7}{24}-\dfrac{2}{13}\)

Ta có: \(\dfrac{19}{37}-\dfrac{31}{24}+\dfrac{-19}{37}+1\dfrac{7}{24}-\dfrac{2}{13}\)

\(=\left(\dfrac{19}{37}+\dfrac{-19}{37}\right)+\left(\dfrac{-31}{24}+1+\dfrac{7}{24}\right)-\dfrac{2}{13}\)

\(=\dfrac{-2}{13}\)

\(\dfrac{19}{37}-\dfrac{31}{24}-\dfrac{-19}{37}+1\dfrac{7}{24}-\dfrac{2}{13}=\dfrac{19}{37}-\dfrac{31}{24}+\dfrac{19}{37}+\dfrac{31}{24}-\dfrac{2}{13}=\left(\dfrac{19}{37}+\dfrac{19}{37}\right)+\left(\dfrac{-31}{24}+\dfrac{31}{24}\right)-\dfrac{2}{13}=\dfrac{38}{31}+0-\dfrac{2}{13}=\dfrac{122}{403}\)

-1/2 + -7/24 + 19/24

=-19/24 + 19/24 =0

-1/2 + -7/24 + 19/24

=-12/24 + -7/24 + 19/24

=-19/24 + 19/24

=0

( 4/9 + 7/9 -  2/9 ) x 19/24  = 1 x 19/24 = 19/24

\(=\dfrac{19}{24}\times\left(\dfrac{4}{9}+\dfrac{7}{9}-\dfrac{2}{9}\right)=\dfrac{19}{24}\times1=\dfrac{19}{24}\)

\(\dfrac{19}{24}\times\left(\dfrac{4}{9}+\dfrac{7}{9}-\dfrac{2}{9}\right)\)

\(=\dfrac{19}{24}\times1=\dfrac{19}{24}\)

\(A=\frac{19}{24}-\frac{1}{2}-\frac{1}{3}-\frac{7}{24}\)

\(A=\frac{19}{24}+\frac{-1}{2}+\frac{-1}{3}+\frac{-7}{24}\)

\(A=\left(\frac{19}{24}+\frac{-7}{24}\right)+\frac{-1}{2}+\frac{-1}{3}\)

\(A=\frac{1}{2}+\frac{-1}{2}+\frac{-1}{3}\)

\(A=0+\frac{-1}{3}=\frac{-1}{3}\)

\(B=\frac{7}{24}+\frac{5}{6}+\frac{1}{4}-\frac{3}{7}-\frac{5}{15}\)

\(B=\frac{7}{24}+\frac{5}{6}+\frac{1}{4}+\frac{-3}{7}+\frac{-1}{3}\)

\(B=\left(\frac{49}{168}+\frac{140}{168}+\frac{42}{168}\right)+\left(\frac{-72}{168}+\frac{-56}{168}\right)\)

\(B=\frac{231}{168}+\frac{-128}{168}=\frac{103}{168}\)

Có: \(A=\frac{-1}{3}=\frac{\left(-1\right)\cdot56}{3\cdot56}=\frac{-56}{168}\)

Mặt khác: \(-56< 103\)

\(\Rightarrow\)\(\frac{-56}{168}< \frac{103}{168}\)

\(hay\) \(A< B\)

\(A=\frac{19}{24}-\frac{1}{2}-\frac{1}{3}-\frac{7}{24}\)

\(A=\frac{19}{24}-\frac{12}{24}-\frac{8}{24}-\frac{7}{24}\)

\(A=\frac{19-12-8-7}{24}\)

\(A=\frac{-8}{24}\)\(=\frac{-1}{3}\)

\(B=\frac{7}{24}+\frac{5}{6}+\frac{1}{4}-\frac{3}{7}-\frac{5}{15}\)

\(B=\frac{7}{24}+\frac{30}{24}+\frac{6}{24}-\frac{3}{7}-\frac{1}{3}\)

\(B=\frac{7}{24}+\frac{30}{24}+\frac{6}{24}-\frac{3}{7}-\frac{8}{24}\)

\(B=\frac{7+30+6-8}{24}-\frac{3}{7}\)

\(B=\frac{21}{24}-\frac{3}{7}\)

\(B=\frac{7}{8}-\frac{3}{7}\)

\(\Rightarrow B=\frac{25}{56}\)

`-3/5 - (-19/24)+ -7/24`

`=-3/5+19/24+ -7/24`

`=-3/5+ (19/24 + - 7/24)`

`=-3/5+ 1/2`

`=-1/10`

\(-\dfrac{3}{5}+\dfrac{19}{24}-\dfrac{7}{24}=\) \(-\dfrac{3}{5}+\dfrac{12}{24}=\) \(-\dfrac{3}{5}+\dfrac{1}{2}\) \(=\dfrac{-6+5}{10}=-\dfrac{1}{10}\)