The Flair Furniture company produces inexpensive tables and chairs. Processes are similar in both require a certain amount of hours of carpentry work and in painting and varnishing department. Each table takes $4$ hours of carpentry and $2$ hours of painting and varnishing. Each chair requires $3$ of carpentry and $1$ hour of painting and varnishing. There are $6$ employees in carpentry that work $40$ hours a week each. There are $5$ employees in painting and varnish that work $20$ hours a week each.

Below is the linear program model in Excel

Given the optimal solution is to produce $20$ Tables and $5$ Chairs, what is the total hours used in the painting and varnish department