Answer:
C. Three
Step-by-step explanation:
We want to solve the equation for n:
14,580 = 20,000(9/10)^n
14580/20000 = 729/1000 = (9/10)^n
(9/10)^3 = (9/10)^n . . . . . . write the left side as a cube
3 = n . . . . . . equate exponents
After year 3, the value will be $14,580.
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You can use logarithms to find n:
log(0.729) = n×log(0.9) . . . . . . taking the log of the 2nd line above
log(0.729)/log(0.9) = n = 3