"Similarly, radioactive decay is like beginning with 100 zillion pennies in a radioactive sample (radioactive isotope atoms) and continuously doing this experiment such that once a half-life, all "pennies" had a chance to flip "
See the link for a comparison of pennies in a cup and decaying atoms.
Feel free to be the first
Please review the linked page for context.
If you can think of something better than this,
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