What is the volume in liters of a 0.760M K3PO4 solution containing 220.9g of potassium phosphate?
mol K3PO4 = grams/molar mass. You have g K3PO4 and molar mass K3PO4, solve for mols K3PO4.
Then M K3PO4 = mols K3PO4/L K3PO4. You have mols and M, solve for L.