Yesterday we talked about germs spreading. Today, the math behind it — and it’s the kind of math that surprises people every single time.
To double a number means to make it twice as big. Watch what happens when we keep doubling!
1 → 2 → 4 → 8. Growing fast!
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Count the dots in each box with me. What’s the pattern?
What comes after 8 if we double one more time?
If one person had germs and gave them to two friends, and they each gave them to two more — how fast would that spread?
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After 8 comes 16! The pattern is each number plus itself. And germs would spread very fast — that’s exactly why washing your hands matters so much.
Try it
Double it! Hold up 1 finger. Now double it — 2 fingers. Double again — 4. Double again — 8. Double again? You’ve run out of fingers! That’s how fast doubling grows.
When something doubles at each step, mathematicians call it exponential growth. It starts slow, then becomes overwhelming — and almost everybody underestimates it.
Barely moves for five rounds — then explodes.
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Read the numbers on the left. Round 5 shows 16 people — why is that bar almost invisible?
Look at rounds 1 through 5. Why would someone watching think “this isn’t a problem”?
The classic puzzle: would you rather have $1,000,000 today, or a penny that doubles every day for 30 days?
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Round 5’s bar is tiny because 16 out of 512 is only about 3% of the scale — it’s real, it’s just dwarfed by what comes later. That’s the trap: the early rounds look harmless because the numbers are small, but the rate was dangerous the whole time. And take the penny: doubling for 30 days gives you over $5,000,000. It’s under $100 after a week, which is exactly why most people guess wrong.
Try it
Run the penny problem! With a partner, calculate it day by day: 1¢, 2¢, 4¢, 8¢… How many days before it passes $100? Before it passes $1,000? Where does the jump actually happen?
Additional Notes/Activities
If additional activities are needed for the Morning Meeting, they will be added here.