Intergalactic Adventure - Challenge 6

Ready for a mathematical space adventure? Complete your Intergalactic Passport Application Form and prepare for a journey to the Planet Turasmara.

Created by Scottish Mathematical Council

An image of a galaxy with red and black colour nuances, and white shining stars.

Challenge 6: Last Card Diner

You've made it to Planet Turasmara, and you're really hungry from your space journey so you stop off at the Our World Diner. One of the pastimes at the Our World Diner is a game called LAST CARD. If you’re going to dine here you need to learn to play!

You will need 16 cards (numbered 1-16).

>> download number cards

Let’s start with JUST the first 4 card for now. Take the cards numbered 1 to 4 only and arrange them in order with the 1 face up on top... then 2 ... then 3 ... finally 4.

Now:

  • Move the top card to the bottom of the pack.
  • Discard the next card.
  • Move the new top card to the bottom of the pack.
  • Discard the next card.
  • Continue like this until you are left with only one card.

What is the number on that card? This is the LAST CARD.

Now try the same with 5 cards (1-5 in order). What do you notice?

Try some different numbers. Can you predict the number of your LAST CARD?

Extra challenge!

What number would be on the LAST CARD if there were 16 cards?.

If you found that easy, try this: if there were 100 cards, what would be the LAST CARD?!

Mission complete!

Congratulations, you have made it to the end of your intergalactic space mission! Did you manage to solve all six challenges? You can check your answers on the next page.

(If you are arriving at the Intergalactic Adventure on this page, you can go back to the Introduction and Challenge 1 to start you off)

Latest News and Events

News

Pi Skyline Art

Create a piece of skyline art to celebrate Pi Day!

News

An Interview with Maisie Chan

To celebrate World Book Day, we’re thrilled to welcome back award-winning Glasgow-based author Maisie Chan. Last year, Maisie joined our Maths Tales programme to discuss her novel Danny Chung Does Not Do Maths and answer questions from enthusiastic pupils. We’ve followed up with Maisie for an exclusive interview, perfect for those who missed the session or had more burning questions.

16th-25th Jun
Event

Museum on the Move - National Museum of Scotland

National Museum of Scotland | | Free
A hands-on workshop where pupils work together to solve a series of maths-related problems based around planning to move one of the display objects at the National Museum of Scotland.