Compound interest formula

Where
A= Future value
P = the Principal (the initial amount of money)
r = annual interest rate
t = time
n= number of times compounded in one t
Remark
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r is generally a percentage like 3%, 7% etc and are applied in the formula as 0.03, 0.07...,
the interest is compounded generally annually (n=1), quarterly (n=4), monthly (n=12), etc...
t is in years,
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Thus, in our problem, P=$200, r=22%=0.22, n=4, t=3
Applying the formula we have:


=380 ($)
Answer: 380$