www.sprinklernewz.us 

2nd Business Model using a profit function when minimum wage is $11.50/ hour.


Profit function is "P(x)" 

P(x) = 3x – 100 

Step 0: Replace the x in the inequality representing the lowest sales (60) and highest sales (130) with P(x) which represents the profit function equation "3x100." 
60 
< 
P(x) 
< 
130 
Step 1: Insert the Profit function in the space in between the inequality representing the lowest daily sales (60) and highest daily sales (130). 
60 
< 
3x  100 
< 
130 
Step 2: Add 100 to both sides of the inequality and the middle term. 
60 +100  < 
3x +100 
< 
130 + 100 
Step 3: Combine like terms with addition. 
160  < 
3x 
< 
230 
Step 4: To get "x" by itself in the middle divide both sides and the middle term by 3. 
160 3 
< 
3x 3 
< 
230 3 
Step 5: Simplify 
54 
< 
x 
< 
77 
This math shows that with higher costs caused by raising minimum wage, between 54 and 77 sandwiches must be sold per day to have a daily profit of between $60 and $130 at $6.50 per sandwich. A way you can check this solution is by entering the profit function in a graphing calculator in the Graph mode, which requires choosing relevant graphingwindow settings that fit the xdomain and yrange of the problem, and then selecting the trace button and tracing along the line of the graph until you reach the x value 54, where you will see a y value of 60 and for x value 77 you will see a yvalue of 130. 

by Andrea Boggs 