a) \(\left(\dfrac{1}{4}x\right):3=\dfrac{5}{6}:\dfrac{1}{8}\\ \left(\dfrac{1}{4}x\right):3=\dfrac{20}{3}\\ \dfrac{1}{4}x=\dfrac{20.3}{3}\\ \dfrac{1}{4}x=20\\ x=80\)

a: Ta có: \(\dfrac{0.25x}{3}=\dfrac{5.6}{0.125}\)

\(\Leftrightarrow x\cdot\dfrac{1}{4}=134.4\)

hay x=537,6

b: Ta có: \(\dfrac{2.5}{7.5}=x:\dfrac{3}{5}\)

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

hay \(x=\dfrac{1}{5}\)

\(\dfrac{5}{2}:\dfrac{15}{2}=x:\dfrac{7}{5}\\ x:\dfrac{7}{5}=\dfrac{1}{3}\\ x=\dfrac{7}{15}\)

0,25x : 3 = \(\frac{5}{6}\) : 0,125

0,25x : 3 = \(\frac{5}{6}\): \(\frac{1}{8}\)

0,25x : 3 = \(\frac{20}{3}\)

0,25x = \(\frac{20}{3}\)x 3

0,25x = 20

x = 20 : 0,25

x = 80

thanks

đáp án là 1,25

mik thề là đúng 100%

tích cho mik nhe!

a, Ta có: 27/x = 9/14
               27/x = 27/42
Vậy x = 42
b, 5/0,18 = 12,5/x
Suy ra 5.x = 0,18 . 12,5
            5.x = 2,25
            x = 2,25 : 5
            x = 0,45 = 9/10
Vậy x = 9/10
c, 0,25x : 3 = 5/6 : 0,125
    1/4x : 3 = 5/6 : 1/8
    1/4x : 3 = 5/6 . 8
    1/4x : 3 = 20/3
    1/4x = 20/3 . 3
    1/4x = 20
    x = 20 : 1/4
    x = 20 . 4
    x = 80
Vậy x = 80
d, x/-15 = -60/x
Suy ra x . x= -15 . (-60)
           x² = 900
           x² = 30² 
Suy ra x=30
Vậy x = 30
Chúc bạn học tốt

cảm ơn bạn nha

Giữ lời hứa nka Nguyễn Mạnh Tân!

làm nhanh mình k cho

Hứa k r lm cko! Bài dài lắm

( 0,25x ) : 3 = 5/6 : 0,125

( 1/4x ) : 3 = 5/6 : 1/8

( 1/4x ) : 3 = 5/6 x 8

( 1/4x ) : 3 = 20/3

1/4x          = 20/3 x 3

1/4x         = 20

x              = 20 : 1/4

x              = 80

0,01 : 2,5 = ( 0,75x ) : 0,75

1/100 : 25/10 = (3/4x) : 3/4

1/100 x 10/25 = (3/4x) : 3/4

=>(3/4x) : 3/4 = 1/250

3/4x                = 1/250 x 3/4

3/4x                = 3/1000

x                     = 3/1000 : 3/4

x                     = 1/250

 4/3 : 0,8 = 2/3 : ( 0,1x )

<=>2/3 : (0,1x) = 4/3 : 0,8

2/3 : (0,1x) = 4/3 : 4/5

2/3 : (0,1x) = 4/3 x 5/4

2/3 : (0,1x) = 5/3

2/3 : (1/10x) = 5/3

1/10x           = 2/3 : 5/3

1/10x           = 2/3 x 3/5

1/10x           = 2/5

x                  = 2/5 : 1/10

x                  = 2/5 x 10

x                  = 4

a) \(\left(0,25x\right):3=\frac{5}{6}:0,125\)

\(\Leftrightarrow0,25x=\frac{20}{3}.3\)

\(\Leftrightarrow x=80\)

b) \(0,01:2,5=\left(0,75x\right):0,75\)

\(\Leftrightarrow x=\frac{1}{250}\)

a, \(\frac{0,25x}{3}=\frac{5}{6:0,125}\Leftrightarrow\frac{0,25x}{3}=\frac{5}{48}\Leftrightarrow12x=15\Leftrightarrow x=\frac{5}{4}\)

b, \(\frac{0,01}{2,5}=\frac{0,75x}{0,75}\Leftrightarrow\frac{3}{400}=\frac{15}{8}x\Leftrightarrow x=\frac{1}{250}\)

\(\left(0,25x\right):3=\frac{5}{6}:0,125\)

=> \(0,25x=\frac{3\cdot\frac{5}{6}}{0,125}=\frac{3\cdot\frac{5}{6}}{\frac{1}{8}}=\frac{5}{2}:\frac{1}{8}=\frac{5}{2}\cdot8=20\)

=> \(x=20:0,25=80\)

Vậy x = 80

b) \(0,01:2,5=\left(0,75x\right):0,75\)

=> \(0,75x=\frac{0,75\cdot0,01}{2,5}=\frac{\frac{3}{4}\cdot\frac{1}{100}}{\frac{5}{2}}=\frac{3}{400}:\frac{5}{2}=\frac{3}{400}\cdot\frac{2}{5}=\frac{3}{1000}\)

=> \(x=\frac{3}{1000}:0,75=\frac{3}{1000}:\frac{3}{4}=\frac{3}{1000}\cdot\frac{4}{3}=\frac{1}{250}\)

Vậy x = 1/250

(0,25x) : 3 = (5/6) : 0,125

⇔ (0,25x).0,125 = 3. (5/6)

⇔ (0,25x).0,125 = 2,5

⇔ 0,25x = 2,5 : 0,125

⇔ 0,25x = 20

⇔ x = 20 : 0,25 = 80