a; \(\dfrac{1919}{2121}\) = \(\dfrac{1919:101}{2121:101}\) = \(\dfrac{19}{21}\)

b; 17 x 5 - \(\dfrac{17}{120}\) - 103

= 85 - \(\dfrac{17}{120}\) - 103

= \(\dfrac{10200}{120}\) - \(\dfrac{17}{120}\) - \(\dfrac{12360}{120}\)

= \(\dfrac{10183}{120}\) - \(\dfrac{12360}{120}\)

= \(\dfrac{-2177}{120}\)

c; 2929 - \(\dfrac{101}{2\times1919}\) + 404

= 2929 - \(\dfrac{1}{38}\) + 404

= \(\dfrac{111302}{38}\) - \(\dfrac{1}{38}\) + \(\dfrac{15352}{38}\)

= \(\dfrac{111301}{38}\) + \(\dfrac{15352}{38}\)

 = \(\dfrac{126653}{38}\)

D

D?

D

2323/4545 = 2323 : 101/4545:101=23/45

đều chia cho 101 nhé

2323:101=23

4545:101=45

phân số còn:23/45

\(\frac{2323}{4545}\)=\(\frac{2323:101}{4545:101}\)=\(\frac{23}{45}\)

Kb vc mk nha !

a) -15/90=-5/30=1/6

120/600=12/60=4/20=1/5

-75/150=-15/30=-5/10=-1/2

b)54/-90=6/-10=3/-5

-180/288=-90/144=-10/16=-5/8

60/-135=20/-45=4/-9

\(\dfrac{150}{225}=\dfrac{2}{3}\)

\(\dfrac{2323}{7575}=\dfrac{23}{75}\)

\(\frac{27272727}{43434343}=\frac{27272727:1010101}{43434343:1010101}=\frac{27}{43}\)

\(\frac{27272727}{43434343}=\frac{27x1010101}{43x1010101}=\frac{27}{43}\)

27272727/43434343=1010101x27/1010101x43=27/43

chắc chắn 100% k cho mình nhata phuong anh

\(A=\dfrac{121212}{131313}+\dfrac{154154}{143143}-\left(\dfrac{2121}{2323}+\dfrac{275275}{253253}\right)\)

\(=\dfrac{12}{13}+\dfrac{14}{13}-\left(\dfrac{21}{23}+\dfrac{25}{23}\right)\)

\(=2-2=0\)

giup ik mà :((
 

1717/2121=17/21

232323/191919=23/19

1.Rút gọn: 27 phần 81 =1phần3.

                 57 phần 76  = 3 phần 4.

                 35 phần 84 = 5 phần 12.          

2.Quy đồng:1 phần 3 = 4 phần 12

                   3 phần tư = 9 phần 12

                   5 phần 12 = 5 phần 12

27/81 = 1/3

57/76 = 3/4

35/84 = 5/12

Quy đồng : 1/3 = 4/12 ; 3/4 = 9/12 còn 5/12 giữ nguyên