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Using the Rule of 72, about how long does money take to double at 8 percent a year?

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  1. 9 years
  2. 12 years
  3. 18 years

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References

  1. Rutgers NJAES: The Rule of 72 njaes.rutgers.edu/sshw/message/message.php?p=Finance&m=349 Checked 2026-10-10.

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