Resistance of a conductivity cell (cell constant \(129 \;m ^{-1}\) ) filled with \(74.5\; ppm\) solution of \(KCl\) is \(100\; \Omega\) (labelled as solution 1). When the same cell is filled with \(KCl\) solution of \(149 \;ppm\), the resistance is \(50\; \Omega\) (labelled as solution 2). The ratio of molar conductivity of solution \(1\) and solution \(2\) is i.e. \(\frac{\wedge_{1}}{\wedge_{2}}=x \times 10^{-3}\). The value of \(x\) is (Nearest integer) Given, molar mass of \(KCl\) is \(74.5 g mol ^{-1}\)

Apply the relevant identity from the chapter and substitute the values established in the previous step, keeping the original constraint in view.

Use the simplified expression to isolate the unknown, then plug the result back into the question setup to confirm the working is internally consistent.

Cross-check against a boundary or limiting case. Both the dimensional balance and the qualitative behaviour at the extreme should agree with the candidate answer.

Combine the steps above to identify the correct option. The remaining choices each fail at least one of the consistency, dimensional, or boundary checks.