Question

There is a juice bar at the gym. Fiona has a gift card that has a balance of $30. Each time she

buys a bottle of her favorite juice, $3 is deducted from her card. Chester also has a gift card.
The equation y=20 - 5x represents y, the balance, in dollars, left on his card after he has
bought x of his favorite bottles of juice.
Who had a greater initial amount of money on their card, Fiona or Chester? Whose balance
decreases at a faster rate every time he or she buys his or her favorite juice? Use the space
below for your work. Explain.

Answer 1

y=mx+b. slopes.

Fiona's equation is y=-3x+30. She will have no money after buying 10 of her favorite drink. She starts with $30 and loses $3 each time. She loses at a slower rate than Chester.

Chester's equation is y=-5x+20. He will have no money after buying 4 of his favorite drink. He starts with $20 and loses $5 each time. He loses at a faster rate than Fiona.