Tammy Giraud owns and operates a restaurant. Her fixed costs are $23,000 per month. She serves luncheons and dinners. The average total bill (excluding tax and tip) is $22 per customer. Giraud's present variable cost is $10.50 per meal.

(1) Determine the formula used to calculate the target number of meals, then calculate how many meals must make $9,200 profit per month with the following changes: rent and other fixed costs rise, $30,920 per month; variable costs rise, $12.40 per meal; increase in average price per meal, $26.

(2) Determine the formula used to calculate the profit per month, then calculate the profit with Giraud may lost 15% of her customers due to the changes in (1). Assume that the restaurant had been serving 2,800 customers per month.

(3) Assume the same situation described in (2). To help offset the anticipated 15% loss of customers, Giraud hires a pianist at $2,400 per month, which increases the total monthly meals from 2,380 to 2,600. At $2,600 customers per month, what is the profit? Would total profit increase or decrease? By how much?