Question

Mark (✓) against the correct answer
If A : B = 5 : 7 and B : C = 6 : 11, then A : B : C = ?

(a) 30 : 42 : 55
(b) 30 : 42 : 77
(c) 35 : 49 : 66
(d) none of these

Answer 1

(b) 30 : 42 : 77


$$\begin{gathered} \frac{A}{B}=\frac{5}{7} \\ \Rightarrow A=\frac{5B}{7}\frac{B}{C}=\frac{6}{11}\Rightarrow C=\frac{11B}{6} \\ \therefore A:B:C=\frac{5B}{7}:B:\frac{11B}{6}=30:42:77 \end{gathered}$$