Respuesta :
The answer is A, just so you know this was the best math class I’ve ever been in
A percentage is a way to describe a part of a whole. The amount paid by Marta for the cookbook is $7.80.
What are Percentages?
A percentage is a way to describe a part of a whole. such as the fraction ¼ can be described as 0.25 which is equal to 25%.
To convert a fraction to a percentage, convert the fraction to decimal form and then multiply by 100 with the '%' symbol.
As it is given that the original price of the cookbook was $13, Marta bought it for 40% off. Therefore, Marta only paid 60% of the original cost,
[tex]\text{Amount paid by Marta} = \text{60\% of the original cost}\\\\\text{Amount paid by Marta} = \dfrac{60}{100} \times \$13\\\\\text{Amount paid by Marta} = \$7.8[/tex]
Thus, the amount paid by Marta for the cookbook is $7.80.
Learn more about Percentages:
https://brainly.com/question/6972121