Respuesta :

Answer:

60 books were at the book sale

Step-by-step explanation:

Let

x = total books at the book sale

Percentage of books sold = 80% of x

= 80/100 * x

= 0.8x

Number of books sold = 48

Therefore,

0.8x = 48

Divide both sides by 0.8

0.8x / 0.8 = 48 / 0.8

x = 60 books

x = total books at the book sale = 60 books

Number of books unsold = Total books at the book sale - number of books sold

= 60 - 48

= 12

Number of books unsold = 12 books