Question

3phần7 nhân x + x = 42 giúp mình nha

 

Answer 1

\(\frac{3}{7}x+x=42\)

\(\Rightarrow\frac{3x}{7}+\frac{7x}{7}=\frac{294}{7}\)

\(\Rightarrow\frac{3x+7x}{7}=\frac{294}{7}\)

\(\Rightarrow10x=294\)

\(\Rightarrow x=29,4\)

Answer 2

\(\frac{3}{7}x+x=45\)
\(\Rightarrow\frac{3}{7}x+\frac{7}{7}x=\frac{245}{7}\)
\(\Rightarrow x\left(\frac{3}{7}+\frac{7}{7}\right)=\frac{245}{7}\)
\(\Rightarrow\frac{10}{7}x=\frac{245}{7}\)
\(\Rightarrow x=\frac{245}{7}:\frac{10}{7}\)
\(\Rightarrow x=\frac{245}{10}\)

Answer 3

\(\frac{3}{7}\).x+x=42
( \(\frac{3}{7}+1\)).x=42
\(\frac{10}{7}\).x=42
x=29,4

Answer 4

29,4 nhé