Bài giải:

( Cho 3.6 : A = 3 : 7 = B : 224 = C : $5\frac{5}{6}$. Tìm A +B + C = ….. ? )

Theo bài ra ta có: $\frac{3.6}{A}==\frac{3}{7}=\frac{B}{224}=\frac{C}{5\frac{5}{6}}$

$\Rightarrow \frac{18}{A}=\frac{3}{7}=\frac{B}{224}=\frac{C}{\frac{35}{6}}$

Do đó: A = $18:\frac{3}{7}=42$

B = $224.\frac{3}{7}=96$

C = $\frac{3}{7}.\frac{35}{6}=\frac{5}{2}$

A + B + C = 42 + 96 + $\frac{5}{2}$ = 140,5

Vậy A + B + C = 140,5