Question

Your school is having a book fair! books cost $5. 50 and magazines cost $3. Genesis bought a total of 7 items and spent a total of $28. 50 at the fair. How many books and how many magazines did she buy?

Answer 1

Let us set up some variables:

b: # of books

m: # of magazines

Let us set up some equations based on the known facts:

• Genesis bought a total of seven books --> b + m = 7
• Genesis spent a total of $28.50 --> 5.5b + 3m = 28.5

Equations:

• b + m = 7 -- equation 1
• 5.5b + 3m = 28.5 -- equation 2

Start Solving:

(Equation 1) * 3

3b + 3m = 21 -- equation 3

(Equation 2) - (Equation 3)

2.5b = 7.5

b = 3 -- equation 4

(Equation 4) plug into (Equation 1)

3 + m = 7

m = 4

Solutions: Genesis bought 3 books and 4 magazines

Hope that helps!