Given that Donna's Cafe has 42 customers representing 20% of the total approved occupancy by the fire department.
a.) According to the fire department's occupancy approval, the percentage of the cafe still available for customers is 100% - 20% = 80%
b.) Given that 42 customers represent 20% of the total approved occupancy by the fire department.
Let the total approved occupancy be x, then 20% of x is 42
i.e.

i.e. the total approved occupancy is 210.
According to the fire department, the number of seats that are still available for customers is given by
