tìm x biết
\(\dfrac{2x}{68}\)=\(\dfrac{16}{32}\)
\(\Leftrightarrow\dfrac{x}{34}=\dfrac{1}{2}\)
\(\Leftrightarrow2x=1.34\)
\(\Leftrightarrow x=17\)
b)\(\dfrac{5x}{100}=\dfrac{105}{25}\)
\(\Leftrightarrow\dfrac{x}{20}=\dfrac{21}{5}\)
\(\Leftrightarrow5x=420\)
\(\Leftrightarrow x=84\)