must be answered with a series/sequences formula
over the past 10 years, the number of CD's sold by a mail order music company has increased an average of 12% per year. If the company sold 1.5 million CD's ten years ago, the total number of sales they have made over all ten years is...?
math B30 - tchrwill, Wednesday, June 16, 2010 at 10:33am
The accumulation of sales over the 10 year period derives from the geometric progression with first term of a = 1,5500,000, the the yearly increase of 12%, or common factor of r = 1.12 and the period of interest, namely n = 10 years.
The sum of the 10 yearly sales is then S = a(r^n - 1)/(r-1) or
S = 1,500,000(1.12^10 - 1)/(1.12 - 1).
I'll let you punch out the numbers.