a )   − 18 − 27 = ( − 18 ) : ( − 9 ) ( − 27 ) : ( − 9 ) = 2 3

b )   45 − 24 = 45 : ( − 3 ) ( − 24 ) : ( − 3 ) = − 15 8

3/5

2/3

9/16

ngu dốt

18/63=2/7

54/12=9/2

27/45=3/5

135/351=15/38

 tk cho mình

\(\frac{18}{63}=\frac{18:9}{63:9}=\frac{2}{7}\)

\(\frac{54}{12}=\frac{54:6}{12:6}=\frac{9}{2}\)

\(\frac{27}{45}=\frac{27:9}{45:9}=\frac{3}{5}\)

\(\frac{135}{315}=\frac{135:45}{315:45}=\frac{3}{7}\)

                                                      18\63 = 2\7

                                                      54/12 = 9\2

                                                      27\45 = 3\5

                                                  135\315 = 3/7

18/27=2/3

24/32=3/4

15/25=3/5

2/3 , 3/4 , 3/5

1) \(\dfrac{5}{10}=\dfrac{5:5}{10:5}=\dfrac{1}{2}\)

\(\dfrac{-18}{-27}=\dfrac{-18:\left(-9\right)}{-27:\left(-9\right)}=\dfrac{2}{3}\)

\(\dfrac{-42}{105}=\dfrac{-42:21}{105:21}=\dfrac{-2}{5}\)

\(\dfrac{75}{-135}=\dfrac{75:\left(-15\right)}{-135:\left(-15\right)}=\dfrac{-5}{9}\)

\(\dfrac5{10}=\dfrac{5.1}{5.2}=\dfrac12\\\dfrac{-18}{-27}=\dfrac{(-9).2}{(-9).3}=\dfrac23\\\dfrac{-42}{105}=\dfrac{21.(-2)}{21.5}=\dfrac{-2}5\\\dfrac{75}{-135}=\dfrac{(-15).(-5)}{(-15).9}=\dfrac{-5}9\)

`5/10=1/2`

`-18/-27=2/3`

-42/105=-2/5`

`75/-135=-5/9``

B

`=>B`

b

52

0.4

2/3

a,52

b,0,4

c,\(\dfrac{2}{3}\)

a 4/5 của 65dm là 52dm
b 24 giây = 2,5 phút
c 18/27 = 2/3

Theo thứ tự : 5/6 ; 2/3 ; 2/3 ; 3/2 ; 2/3 ; 3/8 ; 3/1(hay là 3)

\(\dfrac{10}{12}=\dfrac{5}{6}\)        \(\dfrac{8}{12}=\dfrac{2}{3}\)        \(\dfrac{10}{15}=\dfrac{2}{3}\)        \(\dfrac{27}{18}=\dfrac{3}{2}\)        \(\dfrac{24}{36}=\dfrac{4}{6}=\dfrac{2}{3}\)

\(\dfrac{18}{48}=\dfrac{3}{8}\)        \(\dfrac{42}{14}=\dfrac{6}{2}=\dfrac{3}{1}\)

10/12 = 5/6 

8/12 = 2/3 

10/15 = 2/3 

27/18 = 3/2 

18/48 = 3/8 

42/14 = 3 

a) 15 / 18 = 5/6 ( rút gọn cho 3)

b) 30/120 = 1/4 (rút gọn cho 30)

c) 45 / 27 = 5/3 ( rút gọn cho 9 )

d) 75 / 300 = 1/4 (rút gọn cho 75)

a)là \(\frac{5}{6}\)               b)là \(\frac{1}{4}\)              c)là \(\frac{5}{3}\)                   d)là \(\frac{1}{4}\)

tik nha bạn thân!

a) =  5/6

b) = 1/4

c) = 5/3

d) = 1/4