a) \(1,25:0,8=\frac{3}{8}:0,2x\)

\(\Rightarrow\frac{3}{8}:0,2x=\frac{25}{16}\)

\(\Rightarrow0,2x=\frac{3}{8}:\frac{25}{16}=\frac{6}{25}\)

\(\Rightarrow x=\frac{6}{25}:\frac{1}{5}=\frac{6}{5}\)

b) \(1,8:1,3=\left(-2,7\right):5x\)

\(\Rightarrow\frac{-27}{10}:5x=\frac{18}{13}\)

\(\Rightarrow5x=\frac{-27}{10}:\frac{18}{13}=\frac{-39}{20}\)

\(\Rightarrow x=\frac{-39}{100}\)

25/16=3/8:0,2x

3/8:25/16=0,2x

6/25=0,2x

6/25:0,2=x

6/5=x

giá trị của x thỏa mãn 1,25:0,8 = 3/8 : 0,2x là.........

25/16=3/8 :0,2x

3/8 : 25/16 =0,2x

6/25=0,2x

6/25 : 0,2 = x

6/5 = x

a, \(2,5:4x=0,5:0,2\)

\(\Rightarrow4x=\dfrac{2,5.0,2}{0,5}\)

\(\Rightarrow4x=1\Rightarrow x=\dfrac{1}{4}\)

b, \(\dfrac{1}{5}x:3=\dfrac{2}{3}:0,5\)

\(\Rightarrow\dfrac{1}{5}x=\dfrac{3.\dfrac{2}{3}}{0,5}\)

\(\Rightarrow\dfrac{1}{5}x=4\Rightarrow x=20\)

c, \(1,25:0,8=\dfrac{3}{8}:0,2x\)

\(\Rightarrow0,2x=\dfrac{0,8.\dfrac{3}{8}}{1,25}\)

\(\Rightarrow0,2x=0,24\Rightarrow x=1,2\)

Chúc bạn học tốt!!

a, \(2,5:4x=0,5:0,2\)

\(2,5:4x=2,5\)

\(4x=2,5:2,5\)

\(4x=1\)

\(x=1:4\)

\(x=\dfrac{1}{4}\)

Vậy .............

b, \(\dfrac{1}{5}x:3=\dfrac{2}{3}\)

\(\dfrac{1}{5}x=\dfrac{2}{3}.3\)

\(\dfrac{1}{5}x=2\)

\(x=2:\dfrac{1}{5}\)

\(x=10\)

Vậy .....

c, \(1,25:0,8=\dfrac{3}{8}:0,2x\)

\(1,5625=\dfrac{3}{8}:0,2x\)

\(0,2x=\dfrac{3}{8}:1,5625\)

\(0,2x=0,24\)

\(x=0,24:0,2\)

\(x=1,2\)

Vậy ...

a) \(2,5:4x=0,5:0,2\)

\(\Rightarrow2,5:4x=2,5\)

\(\Rightarrow4x=1\)

\(\Rightarrow x=0,25\)

b) \(\dfrac{1}{5}x:3=\dfrac{2}{3}:0,25\)

\(\Rightarrow\dfrac{1}{5}x:3=\dfrac{8}{3}\)

\(\Rightarrow\dfrac{1}{5}x=8\)

\(\Rightarrow x=40\)

c) \(1,25:0,8=\dfrac{3}{8}:0,2x\)

\(\Rightarrow\dfrac{3}{8}:0,2x=1,5625\)

\(\Rightarrow0,2x=0,24\)

\(\Rightarrow x=1,2\)

\(\dfrac{1.2}{0.8}=\dfrac{3.6}{3x}\)

\(\Leftrightarrow3\cdot x=2.4\)

hay x=0,8

\(\begin{array}{l}4:20 = \frac{4}{{20}} = \frac{1}{5};\\0,5:1,25 = \frac{{0,5}}{{1,25}} = \frac{{50}}{{125}} = \frac{2}{5};\\\frac{3}{5}:\frac{3}{2} = \frac{3}{5}.\frac{2}{3} = \frac{2}{5}\end{array}\)

Như vậy, 2 tỉ số bằng nhau là 0,5 : 1,25 và \(\frac{3}{5}:\frac{3}{2}\)

Tỉ lệ thức: 0,5 : 1,25 = \(\frac{3}{5}:\frac{3}{2}\)