a+b+c+d = 50 a/5=b/4 b/3 = c/7 b/12 = d / 9 tính a,b,c,d

Giải thích các bước giải:

 \(\frac{a}{5}=\frac{b}{4}\)

\( \Leftrightarrow a=\frac{5b}{4}\)

\(\frac{b}{3} =\frac{c}{7}\)

\( \Leftrightarrow c=\frac{7b}{3}\)

\(\frac{b}{12} = \frac{d}{9}\)

\( \Leftrightarrow d=\frac{9b}{12}\)

Ta có:

\(a+b+c+d = 50\)\( \Leftrightarrow \) \(=\frac{5b}{4}+b+\frac{7b}{3}+\frac{9b}{12}=50\)

\( \Leftrightarrow b=\frac{75}{8}=9,375\)

Vậy

\(a=\frac{5.9,375}{4}=\frac{375}{32}\)

\(c=\frac{7.9,375}{3}=\frac{175}{8}\)

\(d=\frac{9.9,375}{12}=\frac{225}{32}\)