Question 1162050
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Future value annuity formula:<br>
{{{A = P((1+(r/n))^(nt)-1)/(r/n)}}}<br>
A = future value
P = periodic contribution
r = annual interest rate
n = number of compounding periods per year
t = time (years)<br>
Note those parameter definitions mean<br>
r/n = periodic interest rate
1+r/n = periodic growth factor
nt = number of compounding periods<br>
In this example,<br>
A = 200,000
P = the unknown
r = 5% = .05
n = 2
t = 12
r/n = .025
1+r/n = 1.025
nt = 24<br>
I'll let you get the practice in doing the calculations....<br>
It's very easy to get ridiculous answers if you get decimal points or parentheses in the wrong place; make sure your answer makes sense.<br>
You should get an answer of a little under $6200.  That makes sense because not counting the interest $6200 every 6 months for 12 years is $6200*24 = $148,800; it's reasonable that the accrued interest will bring that up to the desired $200,000.<br>