Question

A student is selling small and large frozen pizzas for a school fund-raiser.
•The student earns $3 for each small pizza sold
•The student earns $4 for each large pizza sold
•The student has sold exactly 30 pizzas.
•The students has earned $100
How many small pizzas and large pizzas has the student sold?

Answer 1

System of equations:

We'll need one equation for the amount of pizzas, and another for the total cost of the pizzas. In this case, x will represent small pizzas, and y will represent large pizzas.

3x + 4y = 100

x + y = 30

Solving the system of equations:

First, we need to solve for one variable in one equation.

x + y = 30

x = 30 - y

Then, we'll take our equation that is solved for x and plug it into the other equation from above.

3(30 - y) + 4y = 100

Next, we solve for y.

90 - 3y + 4y = 100

90 + y = 100

y = 10

Finally, we take our value for y and plug it back in to the very first equation and solve for x.

x = 30 - 10

x = 20

Answer:

The student has sold 10 large pizzas and 20 small pizzas.

Hope this helps!! :)