Chapter 1.15, Problem 32P

Show that the "doubling time" (time for your money to double) is n periods at

interest rate i% per period With ni = 69, approximately. Show that the error in the approximation is less than 10% if i% < 20%. (Note that n does not have to be the number of years; it can be the number of months with I = interest rate per month, etc.) Hint: You want (1 + i/100)ⁿ 2; take 1n of both sides of this equation and use (13.4). Also see theorem (14.3)