Question

tim 3 so a,b,c biet a+b+c=100 va a:4=b:6=c:5

Answer 1

Áp dụng tính chất của dãy các tỉ số bằng nhau, ta có:

\(\frac{a}{4}=\frac{b}{6}=\frac{c}{5}=\frac{a+b+c}{4+5+6}=\frac{100}{15}=\frac{20}{3}\)

\(\Rightarrow a=\frac{20}{3}.4=\frac{80}{3}\)

\(b=\frac{20}{3}.6=40\)

\(c=\frac{20}{3}.5=\frac{100}{3}\)

Answer 2

\(a:4=b:5=c:6\)

\(\Rightarrow\frac{a}{4}=\frac{b}{5}=\frac{c}{6}=\frac{a+b+c}{4+5+6}=\frac{100}{15}=\frac{20}{3}\)

\(\Leftrightarrow\frac{a}{4}=\frac{20}{3}\)\(\Rightarrow a=\frac{4.20}{3}=\frac{80}{3}\)

\(\Leftrightarrow\frac{b}{5}=\frac{20}{3}\Rightarrow b=\frac{5.20}{3}=\frac{100}{3}\)

\(\Leftrightarrow\frac{c}{6}=\frac{20}{3}\Rightarrow c=\frac{6.20}{3}=40\)

Vậy \(a=\frac{80}{3};b=\frac{100}{3};c=40\)