`2/3=(2xx10)/(3xx10)=20/30`

`3/5=(3xx6)/(5xx6)=18/30`

`7/10=(7xx3)/(10xx3)=21/30`

MSC: 30

\(\dfrac{2}{3}=\dfrac{2\times10}{3\times10}=\dfrac{20}{30}\) 

\(\dfrac{3}{5}=\dfrac{3\times6}{5\times6}=\dfrac{18}{30}\) 

\(\dfrac{7}{10}=\dfrac{7\times3}{10\times3}=\dfrac{21}{30}\)

a) 

\(\dfrac{6}{12}=\dfrac{6:6}{12:6}=\dfrac{1}{2}\)

\(\Rightarrow\dfrac{1}{2}=\dfrac{1\times2}{2\times2}=\dfrac{2}{4}\)

Mà \(\dfrac{2}{4}< \dfrac{3}{4}\)

Vậy \(\dfrac{6}{12}< \dfrac{3}{4}\).

b)

\(\dfrac{8}{10}=\dfrac{8:2}{10:2}=\dfrac{4}{5}\)

Mà \(\dfrac{2}{5}< \dfrac{4}{5}\)

Vậy \(\dfrac{2}{5}< \dfrac{8}{10}\).

c)

\(\dfrac{40}{35}=\dfrac{40:5}{35:5}=\dfrac{8}{7}\)

Mà \(\dfrac{8}{7}>\dfrac{6}{7}\)

Vậy \(\dfrac{40}{35}>\dfrac{6}{7}\).

d)

\(\dfrac{8}{16}=\dfrac{8:8}{16:8}=\dfrac{1}{2}\)

Mà \(\dfrac{1}{2}< \dfrac{5}{2}\)

Vậy \(\dfrac{8}{16}< \dfrac{5}{2}\).

Sau buổi sáng, cửa hàng còn lại:

\(650-170=480kg\) đường

Buổi chiều cửa hàng bán được:

\(\dfrac{5}{8}\times480=300kg\) đường

Cả hai buổi sáng và chiều, cửa hàng bán được:

\(170+300=470kg\)

Cửa hàng còn lại số đường:

\(650-470=180kg\) đường.

\(a,MSC:4\\ \dfrac{1}{2}=\dfrac{1\times2}{2\times2}=\dfrac{2}{4}\)

\(\dfrac{3}{4}\) giữ nguyên

\(2< 3\\ =>\dfrac{1}{2}< \dfrac{3}{4}\)

\(b,MSC:20\\ \dfrac{5}{4}=\dfrac{5\times5}{4\times5}=\dfrac{25}{20}\)

\(\dfrac{15}{20}\) giữ nguyên

\(25>15\\ \Rightarrow\dfrac{5}{4}>\dfrac{15}{20}\)

\(c,MSC:35\\ \dfrac{5}{7}=\dfrac{5\times5}{7\times5}=\dfrac{25}{35}\\ \dfrac{7}{5}=\dfrac{7\times7}{5\times7}=\dfrac{49}{35}\\ 25< 49\\ \Rightarrow\dfrac{5}{7}< \dfrac{7}{5}\)

ac giải giúp em với ạ 

e đang cần gấp ạ 

\(\dfrac{3945}{45}=\dfrac{3945:15}{45:15}=\dfrac{263}{3}\)

\(\dfrac{265}{3}\)

\(\dfrac{100}{33}\) > 1

\(\dfrac{33}{88}\) < 1

\(\dfrac{100}{33}\)> \(\dfrac{33}{88}\)

100/33