In this item, we first solve for the cost of eating in a cafeteria. From the given it is stated that the cost of eating in a fancy restaurant is 3 times the cost of eating in cafeteria. Mathematically,
3x = 36
where x is the cost of eating in cafeteria.
The value of x from the equation is 12.
In a five-day workweek, she eats at the fancy restaurant once and four times in cafeteria. To determine the total cost,
T = 4(12) + 36
T = 84
Thus, the answer to this item is 84.