Spinner Experiment Lab

Pre-Algebra · Axiom Academy

Spin a lopsided wheel a few times and chaos rules. Spin it thousands of times and a hidden order takes over. Two kinds of probability, and the bridge between them Our wheel is built so red fills half of it, blue fills a little under a third, and green takes the rest: in theory red comes up of the time, blue , and green . Those are the theoretical probabilities — what the design promises. But a single spin obeys nothing; it just lands somewhere. So what happens to the actual results when you spin again, and again, and again? Watch the wheel spin without stopping. After each landing the bars below redraw the percentage of spins that hit each color so far. They start jumpy and lopsided — then, spin after spin, every bar drifts onto its dashed expected line. By a few thousand spins the experiment all but matches the theory. A single spin is unpredictable; ten thousand of them are not. That regularity emerging out of randomness is the law of large numbers. Slide the dial to choose how many times we spin. With only a handful, the result is a coin toss of its own — the bars can land far from where the design says they should. Push the count higher and watch the bars lock onto their dashed lines, the largest gap shrinking toward nothing. The largest gap falls off like : to halve the typical error you need about four times as many spins. One spin is a mystery; a million spins is a guarantee

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