One die rolls a flat pattern — every number equally likely. Two dice are different. Some sums are way more common than others. Why?
Count the ways
Sum of 7: (1,6), (2,5), (3,4), (4,3), (5,2), (6,1) — six ways. Sum of 2: only (1,1) — one way. Sum of 12: only (6,6). Seven is the king of two-dice sums.
Flip
Flip a coin and watch heads/tails settle towards 50/50.
Heads
0
Tails
0
H ratio
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Goal: 30% heads, exactly. The more flips, the closer you get.
Roll two dice 100 times and chart the sums. You'll see a triangular distribution peaking at 7 — your first 'normal-ish' curve.