Lucy is going to invest in an account paying an interest rate of 7% compounded daily. How much would Lucy need to invest, to the nearest dollar, for the value of the account to reach $84,000 in 6 years?

Lucy needs to invest $55,194.16

Step-by-step explanation:

The given information are;

The interest rate of the account = 7% compounded daily

The amount at the end of 6 years = $84,000

The time duration = 6 years

The amount Lucy

The formula for compound interest is

Where;

r = The interest rate = 7% = 0.07

n = The number of times a year = 365

t = The number years = 6 years

A(t) =  The amount after 6 years = $84,000

P = The initial amount invested

Therefore, we have;

Therefore, Lucy needs to invest $55,194.16.

ending amount = beginning amount / (2^n)

where "n" = number of half-lives (or elapsed time / half-life)

ending amount = 50 mg / (2 ^10 / 5.3)

ending amount = 50 mg / (2 ^ 1.8867924528)

ending amount = 50 m / 3.6981210597

ending amount = 13.5203794557 mg

or about 13.5 mg remain

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