Question

Tìm x biết:\(\left(4\frac{1}{2}-\frac{2}{5}x\right)\div\frac{7}{4}=\frac{11}{14}\)

Answer 1

\(\left(4\frac{1}{2}-\frac{2}{5}x\right):\frac{7}{4}=\frac{11}{14}\)

\(\left(\frac{9}{2}-\frac{2}{5}x\right)=\frac{11}{14}.\frac{7}{4}=\frac{11}{8}\)

\(\frac{2}{5}x=\frac{9}{2}-\frac{11}{8}\)

\(\frac{2}{5}x=\frac{25}{8}\)

\(x=\frac{25}{8}.\frac{5}{2}=\frac{125}{16}\)

Answer 2

\(\left(4\frac{1}{2}-\frac{2}{5}x\right):\frac{7}{4}=\frac{11}{14}\)

\(\left(\frac{9}{2}-\frac{2}{5}x\right)=\frac{11}{14}x\frac{7}{4}\)

\(\left(\frac{9}{2}-\frac{2}{5}x\right)=\frac{11}{8}\)

\(\frac{2}{5}x=\frac{9}{12}-\frac{11}{8}\)

\(\frac{2}{5}x=\frac{-5}{8}\)

\(x=\frac{-5}{8}:\frac{2}{5}\)

\(x=\frac{-25}{16}\)

Answer 3

-25/16 nha bạn

Answer 4

\(\left(4\frac{1}{2}-\frac{2}{5}x\right):\frac{7}{4}=\frac{11}{14}\)

\(\left(\frac{9}{2}-\frac{2}{5}x\right):\frac{7}{4}=\frac{11}{14}\)

\(\left(\frac{9}{2}-\frac{2}{5}x\right)=\frac{11}{14}.\frac{7}{4}\) 

\(\frac{9}{2}-\frac{2}{5}x=\frac{11}{8}\)

\(\frac{2}{5}x=\frac{9}{2}-\frac{11}{8}\)

\(\frac{2}{5}x=\frac{25}{8}\)

\(x=\frac{25}{8}:\frac{2}{5}\)

\(x=\frac{25}{5}.\frac{5}{2}\)

\(x=\frac{25.5}{5.2}\)

\(x=\frac{25}{2}\)

\(\)

Answer 5

(9/2-2/5x):7/4=11/14

9/2-2/5x=11/14x7/4=11/8

2/5x=9/2-11/8=25/8

x=25/8:2/5= 125/16