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Exponential decay problem

After how many years will \$100 invested at an annual rate of 6% compounded continuously be worth at least 450\$? (Use the formula An=A0e^rt)

• Math -

Your problem is one of "growth" , not decay

100(e^.06t = 450
e^.06t =4.5
.06t lne = ln 4.5
.06t = ln 4.5
t = ln 4.5 / .06 = 25.068 years

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