If 2x - yx + 2y = 1/2 , then value of 3x - y3x + y\, is?

Answer: Option B

$$\begin{array}{rl}& \frac{2x-y}{x+2y}\times \frac{1}{2}\left(\text{Cross multiply}\right)\\ & \Rightarrow 4x-2y=x+2y\\ & \Rightarrow 3x=4y\\ & \Rightarrow x:y=4:3\\ & \therefore \frac{3x-y}{3x+y}\\ & \text{ = }\frac{3\times 4-3}{3\times 4+3}\\ & \text{ = }\frac{12-3}{12+3}\\ & \text{ = }\frac{9}{15}\\ & \text{ = }\frac{3}{5}\end{array}$$