\(\dfrac{14}{21};\dfrac{60}{72}\)

\(\dfrac{60}{72}=\dfrac{5}{6}=\dfrac{5\cdot21}{6\cdot21}=\dfrac{105}{126}\)

\(\dfrac{14}{21}=\dfrac{14\cdot6}{21\cdot6}=\dfrac{84}{126}\)

\(\dfrac{84}{123}< \dfrac{105}{126}\Rightarrow\dfrac{14}{21}< \dfrac{60}{72}\)

\(\dfrac{38}{133};\dfrac{129}{344}\)

\(\dfrac{38}{133}=\dfrac{19}{7}=\dfrac{19\cdot8}{7\cdot8}=\dfrac{152}{56}\)

\(\dfrac{129}{344}=\dfrac{3}{8}=\dfrac{3\cdot7}{8\cdot7}=\dfrac{21}{56}\)

\(\dfrac{152}{56}>\dfrac{21}{56}\Rightarrow\dfrac{38}{133}>\dfrac{129}{344}\)

a: 14/21=2/3=4/6

60/72=5/6

mà 4<5

nên 14/21<60/72

b: 38/133=2/7=16/56

129/344=3/8=21/56

mà 16<21

nên 38/133<129/344

a) `14/21=(14:7)/(21:7)=2/3=4/6`

`60/72=(60:12)/(72:12)=5/6`

Vì `4/6 <5/6`

`=> 14/21 < 60/72`

b) `22/37 = (22:2)/(37:2)= 11/(37/2)`

Vì `54 > 37/2`

`=> 11/54 < 22/37` 

Bài 52 :

a) 14/21 = 2/3 và 60/72 = 5/6

Vì 2/3 = 4/6 < 5/6 nên 2/3 < 5/6

Bài 53 :

a) Vì 200 < 314 nên 17/200 > 17/314

b) Ta có 11/54 < 11/37 < 22/37 nên 11/54 < 22/37

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a: 17/200>17/314

b: 11/54=22/108<22/37

c: 141/893=3/19

159/901=3/17

mà 3/19<3/17

nên 141/893<159/901

\(\left(-\dfrac{5}{11}+\dfrac{7}{22}--\dfrac{4}{33}-\dfrac{5}{44}\right):\left(38\dfrac{1}{22}-39\dfrac{7}{22}\right)\)
\(=\left(-\dfrac{60}{132}+\dfrac{42}{132}+\dfrac{16}{132}-\dfrac{15}{132}\right):\left(\dfrac{837}{22}-\dfrac{865}{22}\right)\)
\(=-\dfrac{17}{132}\cdot\left(-\dfrac{14}{11}\right)\)
\(=\dfrac{119}{726}\)
#AvoidMe

\(=\left(\dfrac{-60}{132}+\dfrac{42}{132}+\dfrac{16}{132}-\dfrac{15}{432}\right):\left(-1-\dfrac{3}{11}\right)\)

\(=\dfrac{-17}{132}\cdot\dfrac{-11}{14}=\dfrac{17}{168}\)

=-17/132*-11/14=17/168

\(\dfrac{54\times107-53}{53\times107+54}=\dfrac{53\times107+53-53}{53\times107+54}=\dfrac{53\times107}{53\times107+54}< 1\)

\(\dfrac{135\times269-133}{134\times269+135}=\dfrac{134\times269+269-133}{134\times269+135}=\dfrac{134\times269+136}{134\times269+135}>1\)

\(\Rightarrow\dfrac{54\times107-53}{53\times107+54}< \dfrac{135\times269-133}{134\times269+135}\)