Answer:
M2(So4)2
Explanation:
Here,
The symbol of metal is M and the symbol of sulphate is So4.
And the,
Valency of metal is 3 and the valency of sulphate is 2..
SO,
M So4
3 2
And when we cross multiply it the formula will be,
M2(So4)2
Hope that it will help u to understand !!