Question

Maria received a $70 gift card for a coffee store. She used it in buying some coffee that cost $8.31 per pound. After buying the coffee, she had $28.45 left on her card. How many pounds of coffee did she buy?

Answer 1

Let x represent the number of pounds of coffee that she bought.

We were told that she bought some coffee, x that cost $8.31 per pound. It means that the cost of x pounds of coffee is $8.31x

After buying the coffee, she had $28.45 left on her card. Since the total amount that she had initially was $70, it means that

8.31x + 28.45 = 70

8.31x = 70 - 28.45

8.31x = 41.55

x = 41.55/8.31

x = 5

She bought 5 pounds of coffee