Question

I went to Half Priced Books and purchased 15 books. I paid $2 each for some and $3 each for the rest of the books. How many $2 books did I buy if I spent $34?

Answer 1

Thus the number of books at $2 is 9 books.

Explanation:

The number of the book purchased = 15 books

Total amount spend to buy the books = $34

The prices of books are $2 and $3.

Let the number of books purchased at price $2 = x

Let the number of books purchased at price $3 = y

Now we have to find the number of books that is bought at $2.

Below are the equations.

x + y = 15

2x + 3y = 34

Now solve for the x,

x + y = 15

y = 15 – x

Now insert it in the 2x + 3y = 34

2x + 3(15-x) = 34

2x + 45 – 3x = 34

-x = 34 – 45

x = 9

Thus the number of books at $2 is 9 books.