Ta có: \(\frac{2}{3}a=\frac{1}{4}b\)
\(\Leftrightarrow\frac{2a}{3}=\frac{b}{4}\)
\(\Leftrightarrow2a=\frac{3b}{4}\)
hay \(a=\frac{3b}{4}:2=\frac{3b}{8}\)
Ta có: \(\frac{1}{2}b=\frac{1}{3}c\)
\(\Leftrightarrow\frac{b}{2}=\frac{c}{3}\)
hay \(c=\frac{3b}{2}\)
Ta có: a+b+c=90
\(\Leftrightarrow\frac{3b}{8}+b+\frac{3b}{2}=90\)
\(\Leftrightarrow b\left(\frac{3}{8}+1+\frac{3}{2}\right)=90\)
\(\Leftrightarrow b\cdot\frac{23}{8}=90\)
hay \(b=90:\frac{23}{8}=\frac{720}{23}\)
Ta có: \(a=\frac{3b}{8}\)(cmt)
hay \(a=3\cdot\frac{720}{23}:8=\frac{270}{23}\)
Ta có: a+b+c=90
\(\Leftrightarrow c=90-a-b=90-\frac{270}{23}-\frac{720}{23}=\frac{1080}{23}\)
Vậy: \(\left(a,b,c\right)=\left(\frac{270}{23};\frac{720}{23};\frac{1080}{23}\right)\)