Question

The Everton College store paid $1727 for an order of 48 calculators. The store paid $10 for each

scientific calculator. The others, all graphing calculators, cost the store $53 each. How many of each type
of calculator was ordered?
The store ordered __ scientific calculators and __ graphing calculators.

Answer 1

To solve this answer, you will need to set up a system of equations.

To do this, first assign variables to your unknown information:

x= scientific calculators

y= graphing calculators

Next, set up 2 equations, one to represent the price paid, and another representing the items bought:

Price: 1727 = 10x + 53y

# of Items: 48 = x + y

With these equations, you can solve this equation in using 2 different tactics: Elimination or Substitution

*This problem is solved using elimination:*

For substitution, one of the variables must cancel out. This is achieved by matching the coefficients next to one of the variables.

Let's choose x. Multiply the equation for number of items by 10, leaving you with a new equation of 480 = 10x + 10y

Now subtract these equations from each other:

1727 = 10x + 53y

- (480 = 10x + 10y)

_______________

1247 = 43y

Now, solve for y by dividing both sides by 43:

y = 29

You now have the number of graphing calculators the store ordered.

To find the number of scientific calculators, plug in y to the equations for the # of items and solve for x:

48 = x + y

48 = x + 29

Subtract both sides by 29: x= 19

The store ordered 19 scientific calculators and 29 graphing calculators