In a ionic compound sulfate why is the ionic number 2- and 4- instead of 2- and 2-

Question

this is as best as i can put it cause i cant write the number wee next to the compund name

Answer 1

sulfate, (SO4)-2  ,  just comes in -2's

someone might have writen it as : SO4-2 & had a typo , writing SO4- instead

here are a few ionic sulfate compounds:

sodium sulfate: Na2SO4   (Na+  &  SO4 2-)

Barium sulfate: BaSO4    (Ba+2  & SO4 2-)

Manganese (IV) sulfate: Mn(SO4)2   (Mn+4  & SO4 2-)

Answer 2

SO (below the line 4) (above the line 2-)

One sulfur atom. Four oxygen atoms. Charge negative 2.