Maya spent 1/5 of her money on a book. if she had $80 left over after she bought the book, how much money did she have originally?

Facts:

Maya spent 1/5 or 20% of her money on a book

She has $80 left over

So that means she has 4/5 of her money left over

First, divide the numerator by the denominator which is 4 divided by 5 which equals .80

Then you get that and divide $80 by .80 which is $100

So that means that she originally had $100 but spent $20 which leaves her with $80

Maya originally had $100