\(\frac{3}{4}\cdot\frac{8}{5}\cdot\frac{5}{9}=\frac{2}{3}\)

\(\frac{3}{7}:\frac{3}{14}:\frac{1}{2}=4\)

cậu ghi lòi  giải ra được không

a) \(\frac{3}{4}x\frac{8}{5}x\frac{5}{9}=\frac{3x8x5}{4x5x9}=\frac{120}{180}=\frac{2}{3}\)

b) \(\frac{6}{7}:\frac{3}{14}:\frac{1}{2}=\frac{6}{7}x\frac{14}{3}x\frac{1}{2}=\frac{84}{42}=2\)

\(\frac{7}{9}\times\frac{3}{5}+\frac{3}{5}\times\frac{5}{6}+\frac{3}{5}\times1\)

\(=\frac{3}{5}\times\left(\frac{7}{9}+\frac{5}{6}+1\right)\)

\(=\frac{3}{5}\times\frac{47}{18}\)

\(=\frac{47}{30}\)

 #hoktot<3# 

\(=\dfrac{3}{4}\left(\dfrac{1}{4}-\dfrac{1}{8}+\dfrac{1}{8}-\dfrac{1}{12}+...+\dfrac{1}{44}-\dfrac{1}{48}\right)\)

\(=\dfrac{3}{4}\cdot\dfrac{44}{48}\)

\(=\dfrac{1}{16}\cdot11=\dfrac{11}{16}\)

`14/9:8/3=14/9xx3/8=[2xx7xx3]/[3xx3xx4xx2]=7/12`

`5/4+9/5xx5/4=5/4+9/4=14/4=7/2`

14/9:8/3=7/12
5/4+9/5x5/4=5/4+9/4=14/4=7/2

14/9x3/8=7/12

5/4+9/4=7/2

a)1/1/4

b)4/2/5

c)3/8

d)1/2/5

9/5 : 7/4 + 3/4 x 8/7       

= (9/5 : 8/7) x (7/4 + 3/4)

= 63/40 x 5/2

= 63/16

7 x 3/14 - 1/14

= 3/2 - 1/4

= 5/4

_{^{\(\dfrac{9}{5}:\dfrac{7}{4}+\dfrac{3}{4}\times\dfrac{8}{7}\)}}

_{^{\(=\dfrac{9}{5}\times\dfrac{4}{7}+\dfrac{3}{4}\times\dfrac{8}{7}\)}}

_{^{\(=\dfrac{36}{35}+\dfrac{6}{7}\)}}

_{^{\(=\dfrac{66}{35}\)}}

_{^{\(7\times\dfrac{3}{14}-\dfrac{1}{14}\)}}

_{^{\(=\dfrac{3}{2}-\dfrac{1}{14}\)}}

_{^{\(=\dfrac{10}{7}\)}}