Math in Our World: Card Collector

Trixtan has a lot of game cards, and he’s always asking for more. He keeps them in two old binders. Each one has 9 cards per page and a total of 48 pages. The binders are completely full, and they’re falling apart.

He wants some new binders, and he found two options:

  • Binder A has 30 pages. Each page holds 12 cards.
  • Binder B has 120 pages. Each page holds only 4 cards.
  1. Use pictures, models, or numbers to show what you know.
  2. What do you notice? What do you wonder?
  3. What math questions can you ask about this situation? Answer all the questions you can!
  • You might sketch an array and use partial products to determine the total number of cards Trixtan has now.
  • How many cards are in one of his old binders? Two of his old binders?
  • Show your work to someone and explain your thinking. Did they understand?
  • Ask whether they have any other questions you can answer!

What if he could buy pages for the binders 10 at a time? How many of each size page would he need to hold his current collection? How many extra pages would you buy for the cards he’ll get in the future?