In a ΔABC, if 4∠A = 3∠B = 12∠C, find ∠A?

Answer: Option C

$$\begin{array}{rl}& 4\angle A=3\angle B=12\angle C\\ & A:B:C=\frac{1}{4}:\frac{1}{3}:\frac{1}{12}\\ & A:B:C=3:4:1\\ & \text{Now}\\ & 3x+4x+x=180\\ & 8x=180\\ & x=\frac{180}{8}\\ & \angle A=3x=\frac{180}{8}\times 3=67.5\end{array}$$