PROBABILITY & RANDOMNESS

Nobody can call where a single bead will land, yet a thousand beads are entirely predictable. Each row of pegs is one coin toss, the final slot is the sum of n left-or-right decisions, so the column heights are precisely the binomial coefficients C(n,k) of Pascal’s triangle. With 16 rows the bell is already smooth, just as the Central Limit Theorem promises, and the band μ ± σ holds about 68% of the beads. Push the rightward probability to 0.65 and the peak slides to n·p: still a bell, merely relocated.

▸ Building the triangular peg array…
▸ Seeding the random number generator
▸ Calibrating the left / right bounce probability
▸ Computing the theoretical normal & binomial curves
▸ Opening the ball valve…
▸ Ready — Online. ✅
0%
⌂ Mathematics

Simulation room Probability & randomness

Probability
Online
Galton board · normal distribution
Live statistics
🎲 Dropping balls…
cumulative distribution · mean
Balls dropped—
Peg rows—
p (right probability)—
Mean (bin)—
Standard deviation—
Tallest bin—
Tip
Each ball is a random walk: at each peg row it bounces left/right. Summing many independent bounces → the pile arranges itself into a normal curve (a bell). Change p to shift the center, add rows to smooth the bell.
—
Click the floor = drop one ball · adjust the sliders on the right to change peg rows, bias & speed
Your browser has canvas disabled.
Goodness-of-fit to the normal curve over time (Law of Large Numbers) empirical fittheory = 100%
About Probability

Nobody can call where a single bead will land, yet a thousand beads are entirely predictable. Each row of pegs is one coin toss, the final slot is the sum of n left-or-right decisions, so the column heights are precisely the binomial coefficients C(n,k) of Pascal’s triangle. With 16 rows the bell is already smooth, just as the Central Limit Theorem promises, and the band μ ± σ holds about 68% of the beads. Push the rightward probability to 0.65 and the peak slides to n·p: still a bell, merely relocated.

Related topics in Mathematics