\(a.\) \(\frac{4}{15}.\frac{7}{9}+\frac{4}{15}.\frac{2}{9}\)

\(=\frac{4}{15}\left(\frac{7}{9}+\frac{2}{9}\right)\)

\(=\frac{4}{15}.\frac{9}{9}\)

\(=\frac{4}{15}.1\)

\(=\frac{4}{15}\)

\(b.\) \(\frac{13}{19}.\frac{23}{11}-\frac{13}{19}.\frac{8}{11}-\frac{13}{19}.\frac{4}{11}\)

\(=\frac{13}{19}\left(\frac{23}{11}-\frac{8}{11}-\frac{4}{11}\right)\)

\(=\frac{13}{19}.\frac{11}{11}\)

\(=\frac{13}{19}.1\)

\(=\frac{13}{19}\)

a)4/15 x(7/9+2/9)=4/15x1=4/15

b)13/19x(23/11-8/11-4/11)13/19x1=13/19

5/10<5/3

13/23<18/19

9/11>23/45

\(\frac{5}{10}< \frac{5}{3}\)

\(\frac{13}{23}< \frac{18}{19}\)

\(\frac{9}{11}>\frac{23}{45}\)

ta chon phan so chung gian la:13/23

ta co:  13/23<13/21 ; 13/23>11/23

=>11/23<13/23<13/21

vay 13/21>11/23

> nha bạn

Để kết quả của phép tính trên là 0 thì :

                 \(\frac{32}{46}\)X x - \(\frac{16}{23}\)X \(\frac{21}{23}\)= 0

                 \(\frac{16}{23}\)X x - \(\frac{16}{23}\)X \(\frac{21}{23}\)= 0

                           \(\frac{16}{23}\)X ( x - \(\frac{21}{23}\)) = 0

                                             x - \(\frac{21}{23}\)= 0 (   chia cả 2 vế cho \(\frac{16}{23}\))

                                                          x = 0 + \(\frac{21}{23}\)

                                                          x = \(\frac{21}{23}\)

Vậy x = \(\frac{21}{23}\)

21/23 nhe

\(\frac{9}{8}>\frac{8}{9}\)

\(\frac{16}{23}>\frac{16}{25}\)

\(\frac{8}{11}< \frac{8}{10}\)

\(\frac{10}{13}>\frac{19}{26}\)

\(\frac{13}{15}< \frac{11}{10}\)

\(\frac{11}{9}=\frac{44}{36}\)

9/8 > 8/9 

16/23 > 16/25 

8/11 < 8/10 

10/13 > 19/26 

13/15 < 11/10 

11/9 = 44/36 

Tham khảo nha !

Chúc bạn học giỏi !

a, \(\frac{6}{7}.\frac{16}{15}.\frac{7}{6}.\frac{21}{32}=\frac{6}{7}.\frac{7}{6}.\frac{16}{15}.\frac{21}{32}\)=\(1.\frac{16}{15}.\frac{21}{32}=\frac{7}{5.2}=\frac{7}{10}\)

Phần b T²

c,\(\frac{7}{4}.\frac{11}{21}+\frac{11}{21}.\frac{5}{4}=\frac{11}{21}.\left(\frac{7}{4}+\frac{5}{4}\right)\)=\(\frac{11}{21}.3=\frac{11}{7}\)

cảm ơn bạn nha

 \(\frac{112}{23}+\frac{345}{23}+\frac{145}{23}+\frac{666}{23}=\left(\frac{112}{23}+\frac{666}{23}\right)+\left(\frac{345}{23}+\frac{145}{23}\right)=\frac{778}{23}+\frac{490}{23}=\frac{1268}{23}\)

Bài 1: Tính giá trị các biểu thức sau:

14 x 3 + 23 x 4

23 x 5 – 96 : 4

16 x 3 + 55 : 5

968 : 8 – 13 x 7

69 : 3 + 21 x 4

36 x 3 – 29 x 2

72 : ( 107 – 99)

5 x (145 – 123)

đề lại bị lỗi

Bài 1: Tính giá trị các biểu thức sau:

14 x 3 + 23 x 4 23 x 5 – 96 : 4 16 x 3 + 55 : 5 968 : 8 – 13 x 769 : 3 + 21 x 4  36 x 3 – 29 x 2 72 : ( 107 – 99) 5 x (145 – 123)

=> Thiếu phép tính