Question

X + 4,9 x 102 = 507,87 

3/4 : X + 1/2 = 5/6

Answer 1

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

Answer 2

\(1)x+4,9\cdot102=507,87\)

\(\Leftrightarrow x+499,8=507,87\)

\(\Leftrightarrow x=507,87-499,8\)

\(\Leftrightarrow x=8,07\)

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=\(\frac{9}{4}\)

Answer 3

\(x+4.9\cdot102=507.87\)

\(x+499.8=507\cdot87\)

\(x=507.87-499.8\)

\(x=8.07\)

\(\frac{3}{4}:x+\frac{1}{2}=\frac{5}{6}\)

\(\frac{3}{4}:x=\frac{5}{6}-\frac{1}{2}\)

\(\frac{3}{4}:x=\frac{1}{3}\)

\(x=\frac{3}{4}:\frac{1}{3}\)

\(x=\frac{9}{4}\)

Answer 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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