Answer:
The minimum number of glasses of lemonade is 70
Step-by-step explanation:
Equations
With the data provided, we can build a model for the profit that Michael gets for selling lemonade.
First, we set up the cost function. He purchased $12 in lemons and $4 in glasses. It makes a fixed cost of $16. He also spends $0.02 per glass of lemonade fot the sugar. Being x the number of glasses of lemonade Michael sells, the total cost is modeled by
C(x)=16+0.02x
The revenue for selling x glasses of lemonade is
R(x)=0.25x
The profit is
P(x)=R(x)-C(x)=0.25x-(16+0.02x)
P(x)=0.23x-16
To make profits:
0.23x-16>0
Solving for x
x>16/0.23
x>69.6
Since x must be an integer
The minimum number of glasses of lemonade is 70