3va1/2 chia 2va1/4
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(a)\text{ Ta có }\frac{2}{3}=\frac{8}{12};\text{ }\frac{1}{4}=\frac{3}{12}\)
\(\frac{8}{12}>\frac{3}{12}\)\(\Rightarrow\frac{2}{3}>\frac{1}{4}\)
\(b)\text{ Ta có }10>8\)
\(\Rightarrow\frac{7}{10}< \frac{7}{8}\)
\(c)\text{Ta có }\frac{3}{5}=\frac{6}{10}\)
\(\text{mà }7< 10\)
\(\Rightarrow\frac{6}{7}>\frac{6}{10}\)
\(\Rightarrow\frac{6}{7}>\frac{3}{5}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(\frac{2}{5}\cdot5\frac{1}{4}-\frac{2}{7}\cdot3\frac{1}{4}\)
= \(\frac{2}{5}\cdot\frac{21}{4}-\frac{2}{7}\cdot\frac{13}{4}\)
= \(\frac{21}{10}-\frac{13}{14}\)
= \(\frac{41}{35}\)
\(\left(2\frac{1}{3}+3\frac{1}{2}\right):\left(-4\frac{1}{6}+3\frac{1}{7}\right)+7\frac{1}{2}\)
= \(\left(\frac{7}{3}+\frac{7}{2}\right):\left(\frac{-25}{6}+\frac{22}{7}\right)+\frac{15}{2}\)
= \(\frac{35}{6}:\frac{-43}{42}+\frac{15}{2}\)
= \(\frac{-245}{43}+\frac{15}{2}\)
= \(\frac{155}{86}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
Bài làm
\(3\frac{1}{2}:2\frac{1}{4}\)
\(=\frac{7}{2}:\frac{9}{4}\)
\(=\frac{7}{2}x\frac{4}{9}\)
\(=\frac{14}{9}\)
# Học tốt #
3va1/2 :2va 1/4 =7/2:9/4=7/2x4/9=14/9