Giải:

\(\dfrac{423}{2813}-\dfrac{5}{6}\)

\(=0,150373267-0,8\left(3\right)\)

\(=-6829600664\)

Vậy ...

\(\dfrac{423}{2813}-\dfrac{5}{6}=\dfrac{2538}{16878}-\dfrac{14065}{16878}=\dfrac{-11257}{16878}\)

em đăng bên box toán để mấy bạn kia trả lời nhé =)))))

Giải:

\(\dfrac{x-2837}{824}+\dfrac{x-2813}{800}+\dfrac{x-1979}{34}+\dfrac{x-1991}{22}=0\)

\(\Leftrightarrow\dfrac{x-2837}{824}+\dfrac{x-2813}{800}+\dfrac{x-1979}{34}+\dfrac{x-1991}{22}+0=0\)

\(\Leftrightarrow\dfrac{x-2837}{824}+\dfrac{x-2813}{800}+\dfrac{x-1979}{34}+\dfrac{x-1991}{22}+2-2=0\)

\(\Leftrightarrow\dfrac{x-2837}{824}+1+\dfrac{x-2813}{800}+1+\dfrac{x-1979}{34}-1+\dfrac{x-1991}{22}-1=0\)

\(\Leftrightarrow\dfrac{x-2837+824}{824}+\dfrac{x-2813+800}{800}+\dfrac{x-1979-34}{34}+\dfrac{x-1991-22}{22}=0\)

\(\Leftrightarrow\dfrac{x-2013}{824}+\dfrac{x-2013}{800}+\dfrac{x-2013}{34}+\dfrac{x-2013}{22}=0\)

\(\Leftrightarrow\left(x-2013\right)\left(\dfrac{1}{824}+\dfrac{1}{800}+\dfrac{1}{34}+\dfrac{1}{22}\right)=0\)

Vì \(\dfrac{1}{824}+\dfrac{1}{800}+\dfrac{1}{34}+\dfrac{1}{22}\ne0\)

Nên \(x-2013=0\)

\(\Leftrightarrow x=2013\)

Vậy \(x=2013\)

Akai HarumaNguyễn Thanh HằngNguyễn NamRibi Nkok NgokRibi Nkok Ngoklê thị hương giangPhạm Hoàng Giang

Hoàng Thị Ngọc AnhNguyễn Huy Tú

\(\dfrac{1}{423}:45,978\approx5,1\)

\(a,A=\dfrac{\dfrac{5}{4}+\dfrac{5}{5}+\dfrac{5}{7}-\dfrac{5}{11}}{\dfrac{10}{4}+\dfrac{10}{5}+\dfrac{10}{7}-\dfrac{10}{11}}\\ =\dfrac{5.\left(\dfrac{1}{4}+\dfrac{1}{5}+\dfrac{1}{7}-\dfrac{1}{11}\right)}{10.\left(\dfrac{1}{4}+\dfrac{1}{5}+\dfrac{1}{7}-\dfrac{1}{11}\right)}\\ =\dfrac{5}{10}\\ =\dfrac{1}{2}\)

Vậy \(A=\dfrac{1}{2}\)

\(b,B=\dfrac{2+\dfrac{6}{5}-\dfrac{6}{7}-\dfrac{6}{11}}{\dfrac{2}{3}+\dfrac{2}{5}-\dfrac{2}{7}-\dfrac{2}{11}}\\ =\dfrac{3.\left(\dfrac{2}{3}+\dfrac{2}{5}-\dfrac{2}{7}-\dfrac{2}{11}\right)}{\dfrac{2}{3}+\dfrac{2}{5}-\dfrac{2}{7}-\dfrac{2}{11}}\\ =3\)

Vậy \(B=3\)

\(\dfrac{1}{2}-\dfrac{2}{3}+\dfrac{3}{4}-\dfrac{4}{5}+\dfrac{5}{6}-\dfrac{6}{7}-\dfrac{6}{5}+\dfrac{4}{5}-\dfrac{3}{4}+\dfrac{2}{3}-\dfrac{1}{2}\)

\(=\left(\dfrac{1}{2}-\dfrac{1}{2}\right)+\left(-\dfrac{2}{3}+\dfrac{2}{3}\right)+\left(\dfrac{3}{4}-\dfrac{3}{4}\right)+\left(-\dfrac{4}{5}+\dfrac{4}{5}\right)+\left(\dfrac{5}{6}-\dfrac{6}{7}-\dfrac{6}{5}\right)\)

\(=0+0+0+0-\dfrac{257}{210}\)

\(=\dfrac{257}{210}\)

Có ai biết câu này không, làm giúp mình với

Cái đó thì chịu.

a: \(\dfrac{1}{8}+\dfrac{5}{8}=\dfrac{1+5}{8}=\dfrac{6}{8}=\dfrac{3}{4}\)

b: \(\dfrac{1}{15}+\dfrac{4}{15}=\dfrac{1+4}{15}=\dfrac{5}{15}=\dfrac{1}{3}\)

c: \(\dfrac{5}{9}+\dfrac{7}{9}=\dfrac{5+7}{9}=\dfrac{12}{9}=\dfrac{4}{3}\)

d: \(\dfrac{23}{100}+\dfrac{27}{100}=\dfrac{23+27}{100}=\dfrac{50}{100}=\dfrac{1}{2}\)

a) 18+58=1+58=68=3418+58=1+58=68=34

b) 115+415=1+415=515=13115+415=1+415=515=13

c) 59+79=5+79=129=4359+79=5+79=129=43

d) 23100+27100=23+27100=50100=12

a) \(\dfrac{3}{4}-\dfrac{1}{8}=\dfrac{6}{8}-\dfrac{1}{8}=\dfrac{6-1}{8}=\dfrac{5}{8}\)

b) \(\dfrac{2}{6}-\dfrac{5}{18}=\dfrac{6}{18}-\dfrac{5}{18}=\dfrac{6-5}{18}=\dfrac{1}{18}\)

c) \(\dfrac{2}{5}-\dfrac{3}{20}=\dfrac{8}{20}-\dfrac{3}{20}=\dfrac{8-3}{20}=\dfrac{5}{20}=\dfrac{1}{4}\)