X+4,9 x 102=507,87
X+499,8=507,87
X=507,87-499,8
X=8,07
3/4:X+1/2=5/6
3/4:X=1/3
X=9/4
\(1)x+4,9\cdot102=507,87\)
\(\Leftrightarrow x+499,8=507,87\)
\(\Leftrightarrow x=507,87-499,8\)
\(\Leftrightarrow x=8,07\)
Vậy x=8,07
\(2)\frac{3}{4}:x+\frac{1}{2}=\frac{5}{6}\)
\(\Leftrightarrow\frac{3}{4}:x=\frac{5}{6}-\frac{1}{2}\)
\(\Leftrightarrow\frac{3}{4}:x=\frac{5}{6}-\frac{3}{6}\)
\(\Leftrightarrow\frac{3}{4}:x=\frac{2}{6}\left(=\frac{1}{3}\right)\)
\(\Leftrightarrow\frac{3}{4}:x=\frac{1}{3}\)
\(\Leftrightarrow x=\frac{3}{4}:\frac{1}{3}\)
\(\Leftrightarrow x=\frac{3}{4}\cdot\frac{3}{1}\)
\(\Leftrightarrow x=\frac{9}{4}\)
Vậy x=\(\frac{9}{4}\)
\(x+4.9\cdot102=507.87\)
\(x+499.8=507\cdot87\)
\(x=507.87-499.8\)
\(x=8.07\)
\(\frac{3}{4}:x+\frac{1}{2}=\frac{5}{6}\)
\(\frac{3}{4}:x=\frac{5}{6}-\frac{1}{2}\)
\(\frac{3}{4}:x=\frac{1}{3}\)
\(x=\frac{3}{4}:\frac{1}{3}\)
\(x=\frac{9}{4}\)
+) \(x+4,9\times102=507,87\)
\(\Rightarrow x+499,8=507,87\)
\(\Rightarrow x=507,87-499,8\)
\(\Rightarrow x=8,07\)
Vậy x = 8,07
+) \(\frac{3}{4}:x+\frac{1}{2}=\frac{5}{6}\)
\(\Rightarrow\frac{3}{4}:x=\frac{5}{6}-\frac{1}{2}\)
\(\Rightarrow\frac{3}{4}:x=\frac{1}{3}\)
\(\Rightarrow x=\frac{3}{4}:\frac{1}{3}\)
\(\Rightarrow x=\frac{9}{4}\)
Vậy \(x=\frac{9}{4}\)
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