1) If we mix up 350g of sugar with some water to make 70% sugar syrup, then
70% of sugar syrup weight is equal to weight of sugar, i.e. 350g
  total weight of sugar syrup will be
350 * 100/70 = 500 g
    2) Similarly, total weight of 30% sugar syrup made with 75g of sugar will be
75 * 100/30 = 250 g