\(\dfrac{12}{11};\dfrac{6}{5};\dfrac{5}{4};\dfrac{4}{3};\dfrac{3}{2}\)

Sắp xếp các phân số sau theo thứ tự tăng dần 12 / 7, 2/3 9/4

\(\frac{2}{3};\frac{12}{7};\frac{9}{4}\)

HT

\(=>\dfrac{1}{6}< \dfrac{2}{3}< \dfrac{5}{5}< \dfrac{5}{4}< \dfrac{19}{12}\)

a,\(\dfrac{1}{6},\dfrac{2}{3},\dfrac{5}{5},\dfrac{5}{4},\dfrac{19}{12}\)

b,\(\dfrac{8}{11}\)\(x=\dfrac{1}{5}\)

\(x=\dfrac{1}{5}:\dfrac{8}{11}\)

\(x=\dfrac{11}{40}\)

a) -12,13; -2,4; -2,3; 0,5; 2,4

b) 2,999; 2,9; -2,9; -2,999

a) -12,13; -2,4; -2,3; 0,5; 2,4

b) 2,999; 2,9; -2,9; -2,999

a) -12,13; -2,4; -2,3; 0,5; 2,4

b) 2,999; 2,9; -2,9; -2,999

3/20; 6/15; 9/12

-5/8=-15/24=-30/48

-9/16=-27/48

-2/3=-32/48

-7/12=-28/48

=>-2/3<-5/8<-7/12<-9/16

\(\dfrac{3}{5}=\dfrac{36}{60};\dfrac{3}{4}=\dfrac{45}{60};\dfrac{7}{12}=\dfrac{35}{60}\\ \dfrac{35}{60}< \dfrac{36}{60}< \dfrac{45}{60}\Rightarrow\dfrac{7}{12}< \dfrac{3}{5}< \dfrac{3}{4}\)

Sắp xếp theo thứ tự từ bé đến lớn 

9/5;1/6;15/7

Ta có: \(-\frac{12}{7}<\frac{-7}{7}=-1\)

\(-1=\frac{-40}{40}<\frac{-35}{40}<\frac{-24}{40}\)

=>\(-1<-\frac78<-\frac35\)

Do đó: \(-\frac{12}{7}<-1<-\frac78<-\frac35<0\) (1)

Ta có: \(\frac25=\frac{2\cdot6}{5\cdot6}=\frac{12}{30};\frac{13}{5}=\frac{13\cdot6}{5\cdot6}=\frac{78}{30}\)

\(\frac{7}{15}=\frac{7\cdot2}{15\cdot2}=\frac{14}{30};1=\frac{1\cdot30}{30}=\frac{30}{30};\frac92=\frac{9\cdot15}{2\cdot15}=\frac{135}{30}\)

mà \(\frac{12}{30}<\frac{14}{30}<\frac{30}{30}<\frac{78}{30}<\frac{135}{30}\)

nên \(0<\frac25<\frac{7}{15}<1<\frac{13}{5}<\frac92\) (2)

Từ (1),(2) suy ra \(-\frac{12}{7}<-1<-\frac78<-\frac35<0<\frac25<\frac{7}{15}<1<\frac{13}{5}<\frac92\)