Answer:
Part A
0.15·x + 3 = 18.50
Part B
0.65·x + 3 - y = 21.00
Part C
The equation in part A gives the total revenue of the yard sale, while the equation in part B gives the profit of the yard sale
Step-by-step explanation:
Part A
The total amount Sydney made selling lemonade = $18.50
The amount she sold a cup of lemonade = $0.50
The amount she received as tip from a neighbor = $3
Let <em>x </em>represent the number of cups sold, we have;
0.15·x + 3 = 18.50
Part B
The profit Daria made = 21.00
The price per cup of lemonade = $0.75
The amount she received as tip = $3
The cost of each plastic cup = $0.10
Let x<em> </em>represent the number of cups sold, we have;
0.75·x - 0.1·x + 3 - y = 21.00
∴ 0.65·x + 3 - y = 21.00
Where;
y = The cost of making the lemonade
Part C
The difference in the two equation is that the first equation relates to total revenue, while the second equation takes account of the costs of the cup and he lemonade