If you dissolve 50g of sugar in 30g of water (it is possible!) what would be the sugar concentration?

in mass or percent weight (%w); the concentration would be :
[tex]100 * \frac{MassSolute}{MassSolution} = PercentWeight [/tex]

100 * 50 / (50 + 30) = 100 * 50/80 = 62.5 %w