Concept explainers
Time to Double or Triple an Investment The formula can be used to find the number of years required to multiply an investment times when is the per annum interest rate compounded times a year.
(a) How many years will it take to double the value of an IRA that compounds annually at the rate of ?
(b) How many years will it take to triple the value of a savings account that compounds quarterly at an annual rate of ?
(c) Give a derivation of this formula.
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Precalculus (10th Edition)
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