Moist air at $105$ kPa, $30^\circ C$ and $80\%$ relative humidity flows over a cooling coil in an insulated air-conditioning duct. Saturated air exits the duct at $100$ kPa and $15^\circ C$. The saturation pressures of water at $30^\circ C$ and $15^\circ C$ are $4.24$ kPa and $1.7$ kPa respectively. Molecular weight of water is $18$ g/mol and that of air is $28.94$ g/mol. The mass of water condensing out from the duct is ______ g/kg of dry air (round off to the nearest integer).