( x.100-0,7357):0,01 = 0,55 + 15,88 

(x.100-0,7357) : 0.01= 16,43

x.100-0,7357 = 16,43.0,01

x.100-0,7357=0,1643

x.100=0,1643+0,7357

x.100= 0,9

x=0,9: 100

x=0,009 

Tick cho mình nhé :*

( x.100-0,7357):0,01 = 0,55 + 15,88 

(x.100-0,7357) : 0.01= 16,43

x.100-0,7357 = 16,43.0,01

x.100-0,7357=0,1643

x.100=0,1643+0,7357

x.100= 0,9

x=0,9: 100

x=0,009 

Tick cho mình nhé :*

(X.100-0,7357):0,01-15,88=0,55

=>(X.100-0,7357):0,01=0,55+15,88

=>(X.100-0,7357):0,01=16,43

=>X.100-0,7357=16,43.0,01

=>X.100-0,7357=0,1643

=>X.100=0,1643+0,7357

=>X.100=0,9

=>X=0,9:100

=>X=9/1000=0,009

\(a.\left(y.100-0,7357\right):0,01=0,55+15,88\)

\(\Leftrightarrow\left(100y-0,7357\right):0,01=16,43\)

\(\Leftrightarrow100y-0,7357=0,1643\)

\(\Leftrightarrow100y=0,9\)

\(\Leftrightarrow y=\frac{9}{1000}\)

\(b.14:\left(0,4+\frac{0,16}{y}\right)=7\)

\(\Leftrightarrow0,4+\frac{0,16}{y}=2\)

\(\Leftrightarrow\frac{0,16}{y}=1,6\)

\(\Leftrightarrow x=0,1\)

\(c.520+7,5.4=y+\frac{175}{5}+30\)

\(\Leftrightarrow520+30=y+65\)

\(\Leftrightarrow550=y+65\)

\(\Leftrightarrow y=485\)

Câu 2: 

312:0,1=3120

312x0,01=3,12

235

y là 235

235.678