We are given the following molar conductance values:
- \( \lambda_m(\text{KCl}) = 152 \, \text{cm}^2 \, \text{ohm}^{-1} \)
- \( \lambda_m(\text{HCl}) = 425 \, \text{cm}^2 \, \text{ohm}^{-1} \)
- \( \lambda_m(\text{CH}_3 \text{COOK}) = 91 \, \text{cm}^2 \, \text{ohm}^{-1} \)
The molar conductance of \( \text{CH}_3 \text{COOH} \) at infinite dilution can be found using the relationship:
\[
\lambda_m (\text{CH}_3 \text{COOH}) = \lambda_m (\text{CH}_3 \text{COOK}) + \lambda_m (\text{HCl}) - \lambda_m (\text{KCl})
\]
Substituting the given values:
\[
\lambda_m (\text{CH}_3 \text{COOH}) = 91 + 425 - 152 = 364 \, \text{cm}^2 \, \text{ohm}^{-1}
\]
Thus, the molar conductance of \( \text{CH}_3 \text{COOH} \) at infinite dilution is 364 cm\(^2\) ohm\(^{-1}\).