a) \(\frac{x}{27}=\frac{-2}{3,6}\Leftrightarrow x=\frac{-2.27}{3,6}=-15\)

b) \(\frac{4\frac{1}{4}}{2\frac{7}{8}}=\frac{x}{1,61}\Leftrightarrow\frac{4,25}{2,875}=\frac{x}{1,61}\Leftrightarrow x=\frac{4,25.1,61}{2,875}=2,38\)

a) \(\frac{x}{27}=-\frac{2}{3,6}\Rightarrow x=\frac{-2.27}{3,6}=-15\)

b) \(\frac{4\frac{1}{4}}{2\frac{7}{8}}=\frac{x}{1,61}\Rightarrow\frac{\frac{17}{4}}{\frac{23}{8}}=\frac{x}{1,61}\Leftrightarrow\frac{17}{4}\cdot\frac{8}{23}=\frac{x}{1,61}\)

 \(\frac{34}{23}=\frac{x}{1,61}\Rightarrow x=\frac{1,61.34}{23}=2,38\)

a) Ta được: x . 1,25 = 5. (-2) nên \(x = \frac{{5.( - 2)}}{{1,25}} =  - 8\)

Vậy x = -8

b) Vì 18 : x = 2,4 : 3,6 nên \(\frac{{18}}{x} = \frac{{2,4}}{{3,6}} \Rightarrow 18.3,6 = x.2,4 \Leftrightarrow x = \frac{{18.3,6}}{{2,4}} = 27\)

Vậy x = 27

c) Vì (x+1) : 0,4 = 0,5 : 0,2 nên \(\frac{{x + 1}}{{0,4}} = \frac{{0,5}}{{0,2}} \Rightarrow (x + 1).0,2 = 0,4.0,5 \Leftrightarrow x + 1 = \frac{{0,4.0,5}}{{0,2}} = 1 \Leftrightarrow x = 0\)

Vậy x = 0

a, x= (-2). 5 :1,25 = -8

b, x= 18 : (2,4:3,6)= 18: 2/3 = 18 x 3/2 = 27

c, x+1= (0,5:0,2) x 0,4= 2,5 x 0,4= 1

=> x=1-1=0

a)\(\frac{x}{27}=\frac{-2}{3,6}\)

=>x.3,6=27.(-2)

=>x.3,6=-54

=>x=-15

b)-0,52:x=-9,36:16,38

=>-0,52:x=-4/7

=>x=0,91

c)\(\frac{4\frac{1}{4}}{2\frac{7}{8}}=\frac{x}{1,61}\)

=>\(2\frac{7}{8}.x=4\frac{1}{4}.1,61\)

=>\(2\frac{7}{8}.x=\frac{2737}{400}\)

=>x=\(\frac{119}{50}\)

a,\(\frac{x}{27}=-\frac{2}{3,6}\)

\(\Leftrightarrow x.3,6=27.-2\)

\(\Leftrightarrow x.3,6=-54\)

\(\Leftrightarrow x=-15\)

b,\(-0,52\div x=-9,36\div16,38\)

\(\Leftrightarrow-0,52\div x=-\frac{4}{7}\)

\(\Leftrightarrow x=\frac{91}{100}\)

c,\(\frac{4\frac{1}{4}}{2\frac{7}{8}}=\frac{x}{1,61}\)

\(\Leftrightarrow\frac{4,25}{2,875}=\frac{x}{1,61}\)

\(\Leftrightarrow x.2,875=4,25.1,61\)

\(\Leftrightarrow x.2,875=6,8425\)

\(\Leftrightarrow x=2,38\)

a, ta có:27:3,6=7,5

=>-2x7,5=15

vậy x cần tìm là 15

b, -0,52:x=\(-\frac{4}{7}\)

\(\frac{-13}{25}\): x=\(\frac{-4}{7}\)

x=\(\frac{-13}{25}:\frac{-4}{7}\)

x=0,91

Lời giải:

a.

$x:27=-2:3,6=\frac{-5}{9}$

$x=27.\frac{-5}{9}=-15$

b.

$\frac{2x+1}{-27}=\frac{-3}{2x+1}$

$\Rightarrow (2x+1)^2=(-27)(-3)=81=9^2=(-9)^2$

$\Rightarrow 2x+1=9$ hoặc $2x+1=-9$

$\Rightarrow x=4$ hoặc $x=-5$

a,x/27=-2/3,6                      b,-0,52:x=-9,36:16,38

=)) x.3,6=27.(-2)                     -0,52:x=-4/7

=)) x.3,6=-54                            x=-0,52:(-4/7)

=)) x=-15                                   x=0,91

a)x/27=-5/6

x=-5/6.27

x=-15