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At the end of each month, Jacob puts \$400 into an account that pays 6%, compounded semi-annually. Use your graphing calculator to determine how much Jacob will have after 25 years? Show how you obtained your answer by filling in the following as if it was the calculator display.
This is how I filled the TVM Solver on my TI83plus. However I was told it is wrong. I also figured it out using the formula A=P(1+I)^n so A= 400(1+0.03)^50 =\$1753.56 As you can see I have different results and I'm extremely confused. What am I doing wrong in filling in the TVM Solver

N=50
I%=6
PV=0
PMT=-400
FV=?answer I got 22622.76185
P/Y=12
C/Y=2
PMT:END BEGIN

Not familiar with the way the calculator is set up to do this, but the problem here is that the payments are monthly and the rate is compounded semiannually

So the old-fashioned way is to find the equivalent monthly rate

let the monthly rate be i
(1+i)^12 = (1.03)^2
1+i = 1.03^(1/6) = 1.0049386

so i = .0049386
n = 12*25 = 300
payment = 400

Using the standard formula for the "amount of an annuity"
amount = 400 [ 1.0049386^300 - 1 ]/.0049386
= 270 076.94

What you found was the value of the first payment of \$400 twenty five years from now