9514 1404 393
Answer:
21.6 years
Step-by-step explanation:
The first statement tells you the account balance can be modeled by ...
A = 440(2)^(t/8) . . . . . where t is in years
We want to find t when A = 2860
2860 = 440(2^(t/8))
6.5 = 2^(t/8) . . . . . . . . . . divide by 440
log(6.5) = (t/8)log(2) . . . . take logarithms
t = 8·log(6.5)/log(2) ≈ 21.604 . . . . . . divide by the coefficient of t; evaluate
It would take about 21.6 years for the value to reach $2,860.
