About this game
CS • KS3 • Number Systems

Connolly's Count Like a Computer is a classroom-friendly game where you practise binary, denary, and hexadecimal.

Questions fall from the top of the screen. Copy the calculation into your book, work it out using place-value rules, then type your answer before it hits the danger line.

You can choose conversions between binary and denary, arithmetic in binary, stretch yourself with hexadecimal, or try to survive Master Mode.

• Binary → only 0 and 1
• Denary → digits 0–9
• Hex → digits 0–9 and letters A–F
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Quick Reference
Binary Addition
1 + 0 → 1 0 + 1 → 1 1 + 1 → 0 carry 1 1 + 1 + 1 → 1 carry 1
Binary Subtraction
1 − 0 → 1 1 − 1 → 0 0 − 1 → borrow (worth 2)
Hex Digits
0 1 2 3 4 5 6 7 8 9 A B C D E F
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