The stoichiometric reaction of \( 516 \, \mathrm{g} \) of dimethyldichlorosilane with water results in a tetrameric cyclic product \( X \) in \( 75\% \) yield. The weight \( (\text{in g}) \) of \( X \) obtained is _______.
[Use, molar mass \( (\mathrm{g \, mol^{-1}}) \): \( \mathrm{H} = 1 \), \( \mathrm{C} = 12 \), \( \mathrm{O} = 16 \), \( \mathrm{Si} = 28 \), \( \mathrm{Cl} = 35.5 \)]
