What is the correct formula for Molybdenum 4 Phosphate?

Molybdenum (IV) phosphate's formula is: Mo3(PO4)4

Molybdenum (IV) has four valence electrons, which it will lose, being a metal. The phosphate polyatomic ion, PO4, needs three electrons. In order for the charges to cancel each other out, you need 3 Mo's and 4 phosphates, which you apply with the subscripts shown above.