What expression represents 7 plus 7 plus 7 plus 7

When is g(x) = 0 for the function g(x) = 5.23x + 4?

Atotal of 766 tickets were sold for the school play. they were either adult tickets or student tickets. there were 66 more student tickets sold than adult tickets. how many adult tickets were sold?

According to the general equation for conditional probability if p(anb)=3/7 and p(b)=7/8 what is p(a i b)