X : 6 x 7,2 + X x 1,3 + X : 2 + 15 = 19,95
X x \(\frac{1}{6}\) x \(\frac{36}{5}\)+ X x \(\frac{13}{10}\)+ X x \(\frac{1}{2}\) = 19,95 - 15 = 4,95 = \(\frac{99}{20}\)
X x \(\frac{6}{5}\)+ X x \(\frac{13}{10}\)+ X x \(\frac{1}{2}\)= \(\frac{99}{20}\)
X x ( \(\frac{6}{5}+\frac{13}{10}+\frac{1}{2}\)) = \(\frac{99}{20}\)
X x 3 = \(\frac{99}{20}\)
X = \(\frac{99}{20}:3\)
X = \(\frac{33}{20}\)
X : 6 x 7,2 + 1,3 x X + X : 2 + 15 = 19,95
(X x 7,2) / 6 + (7,8 x X) / 6 + (X x 3) / 6 + 90/6 = 119,7/6
X x 7,2 + 7,8 x X + X x 3 + 90 = 119,7
X x (7,2 + 7,8 + 3) = 119,7 - 90
X x 18 = 29,7
X = 29,7 : 18
X = 1,65
X : 6 x 7,2 + 1,3 x X + X : 2 + 15 = 19,95
(X x 7,2) / 6 + (7,8 x X) / 6 + (X x 3) / 6 + 90/6 = 119,7/6
X x 7,2 + 7,8 x X + X x 3 + 90 = 119,7
X x (7,2 + 7,8 + 3) = 119,7 - 90
X x 18 = 29,7
X = 29,7 : 18
X = 1,65
\(x\div6\times7,2+x\times1,3+x\div2+15=19,95\)
\(x\times\frac{1}{6}\times\frac{36}{5}+x\times\frac{13}{10}+x\times\frac{1}{2}=19,95-15=\frac{99}{20}\)
\(x\times\frac{6}{5}+x\times\frac{13}{10}+x\times\frac{1}{2}=\frac{99}{20}\)
\(x\times\left(\frac{6}{5}+\frac{13}{10}+\frac{1}{2}\right)=\frac{99}{20}\)
\(x\times3=\frac{99}{20}\)
\(x=\frac{99}{20}\div3\)
\(x=\frac{33}{20}\)
\(x\frac{1}{6}.7,2+x.1,3+x.\frac{1}{2}+15=19,95\)
\(x\left(\frac{1}{6}.7,2+1,3+\frac{1}{2}\right)=19,95-15\)
\(x.3=4,95\)
\(x=\frac{4,95}{3}=1,65\)
Vậy \(x=1,65\)