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Five cards, one rule
Each card has twice as many dots as the card to its right. Tap a card to flip it. Dots showing means 1. Card face down means 0. Add up the dots you can see.
Things to try
- What is the biggest number you can make with five cards?
- Can you make every number from 0 up to that number? Is there only one way to make each one?
- Leibniz would add a sixth card on the left. How many dots should it have?
Make the numbers
Choose a number, flip the cards to make it, then check. Write the binary code on your mission sheet too.
Decode the message
A secret agent sent ten codes. Set the cards to match the code, read the number, then find its letter in the chart (A = 1, B = 2 … Z = 26).
Code
My name in binary
Type your first name, then build it in binary. For each letter, find its number in the chart and flip the small cards to make that number. Press Check. When your binary is right, the letter appears on the left.
Your name stays on this screen. It is not saved or sent anywhere.
Swap with a partner
When your whole name is built, turn on secret mode. Can a partner read your name from the cards alone?
More bits, more numbers
Each card is called a bit (binary digit). Add more bits and watch what happens to how many patterns you can make.
Spot the pattern
Fill in the two missing rows, then check. Look at how each row compares with the one above.
Eight bits together are called a byte. One byte can store 256 different patterns: enough for every letter, digit and symbol on a keyboard.
Mission 2 complete
You counted, decoded and built your name in binary, just like Leibniz in 1679. Show your teacher this screen and your mission sheet.