Jill spent 12% of her money on a book. After buying the book, she had $120.12. How much money did Jill have before buying the book?

Jill had $136.50 before buying the book.

Step-by-step explanation:

Let x be the total amount that Jill had

Then 12% of x is 0.12x

Jill was left with $120.12 after buying the book

Subtracting the cost of book from the total amount will given us the remaining amount.

Which means

Hence,

Jill had $136.50 before buying the book.

y=mx+b is the final answer!   : )