An element forms an oxide, in which the oxygen is 20% of the oxide by weight, the equivalent weight of the given element will be

In metal oxideO = 20%M = 80%If 20 g of oxygen associates with 80 g, then 8 g of oxygen associates with metal8020 × 8 = 32  g of metal ∴  Eq.  wt. of metal = 32 g