Question

[Minamoto Sizuka]

tìm a,b,c biết:\(\frac{1}{2}a=\frac{2}{3}b=\frac{3}{4}c\)và \(a-b=15\)

giúp mk vs nha, mk sẽ cho 1 tikc

Answer 1

[Doraemon]

ta có:\(\frac{1}{2}a=\frac{2}{3}b=\frac{3}{4}c\)\(\Rightarrow\frac{1}{2}\times a\times\frac{1}{6}=\frac{2}{3}\times b\times\frac{1}{6}=\frac{3}{4}\times c\times\frac{1}{6}\)

\(\Rightarrow\frac{a}{12}=\frac{b}{9}=\frac{c}{8}=\frac{a-b}{12-9}=\frac{15}{3}=5\)

\(\Rightarrow\frac{a}{12}=5\Rightarrow a=12\times5=60\)

\(\Rightarrow\frac{b}{9}=5\Rightarrow b=9\times5=45\)

\(\Rightarrow\frac{c}{8}=5\Rightarrow c=8\times5=40\)

chúc bạn học tốt!!

Answer 2

[Chu Công Đức]

\(\frac{1}{2}a=\frac{2}{3}b=\frac{3}{4}c=\frac{a}{2}=\frac{2b}{3}=\frac{3b}{4}\)

\(\Rightarrow\frac{a}{2.6}=\frac{2b}{3.6}=\frac{3c}{4.6}=\frac{a}{12}=\frac{b}{9}=\frac{c}{8}=\frac{a-b}{12-9}=\frac{15}{3}=5\)

\(\Rightarrow a=5.12=60\); \(b=5.9=45\); \(c=5.8=40\)

Vậy \(a=60\), \(b=45\), \(c=40\)