Brain Teasers & Mental Math
What is 2^10, and why is it a useful anchor for compounding math?
Model answer
2^10 = 1,024 ≈ 1,000.
So 10 doublings multiply money roughly 1,000×. Chain this with the rule of 72: at 7.2% a year, money doubles every ~10 years, so over a century that's ~10…
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