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Im doing my math homework and this question came up, and i dont know what to do. Can someone please help?

Im doing my math homework and this question came up, and i dont know what to do. Can-example-1
User Sariii
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1 Answer

3 votes
Data:
P = 5.300,00
A = 7.000,00
r = 9% = 0,09
n = 4
t = ?

We have the following compound interest formula:


A = P*(1+ (r)/(n))^(nt)

7000 = 5300*(1+ (0.09)/(4))^(4t)

7000 = 5300*(1+ 0.0225)^(4t)

7000 = 5300*(1.0225)^(4t)

(1.0225)^(4t) = (7000)/(5300)

(1.0225)^(4t) = 1.32075
Now, take the natural logarithm of both sides:

ln(1.0225^(4t)) = ln(1.32075)

4*t*ln(1.0225) = = ln(1.32075)

4*t = (ln(1.32075))/(ln(1.0225))

4t = 12.50301769...

4t \approx 12.50302

t \approx (12.50302)/(4)

\boxed{t \approx 3.1258years}

Therefore, we have: (answer)

3 years 1 month and 16 days
User FooMonster
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