Asked by Elcia
                Joseph is 28 and would like to retire at 55. He has $25,000 to invest today and would like to have $1,000,000 in his retirement account when he retires. Joseph has found an investment that will pay him a return of 6% until retirement. How much will Joseph have to invest each month in order to reach his retirement?
            
            
        Answers
                    Answered by
            MathMate
            
    Use the mortgage formula:
Future value = FV = 1000000
payment per period = P (to be found)
rate of interest (per period) = i (0.06/12=0.005 per month)
R = 1+i = integrated rate = 1.005
n = number of periods = (55-28)*12=324
then
FV=P(1+R+R²+R³+....+R<sup>n-1</sup>)
=P(R^n-1)/(R-1)
1000000=P(1.005^324-1)/(.005)
=>
P=1000000*.005/(1.005^324-1)
=1239.85
Note: because of rounding, the FV of the above answer will be missing almost $3, while 1239.86 will yield an FV of $5.2 in excess.
    
Future value = FV = 1000000
payment per period = P (to be found)
rate of interest (per period) = i (0.06/12=0.005 per month)
R = 1+i = integrated rate = 1.005
n = number of periods = (55-28)*12=324
then
FV=P(1+R+R²+R³+....+R<sup>n-1</sup>)
=P(R^n-1)/(R-1)
1000000=P(1.005^324-1)/(.005)
=>
P=1000000*.005/(1.005^324-1)
=1239.85
Note: because of rounding, the FV of the above answer will be missing almost $3, while 1239.86 will yield an FV of $5.2 in excess.
                    Answered by
            Reiny
            
    What about the initial $25,000 that he starts with ?
i = .06/12 = .005
25000(1.005)^324 + R(1.005^324 - 1)/.005 = 1,000,000
R(806.5468...) = 874,181.64
R = $1083.86
    
i = .06/12 = .005
25000(1.005)^324 + R(1.005^324 - 1)/.005 = 1,000,000
R(806.5468...) = 874,181.64
R = $1083.86
                    Answered by
            MathMate
            
    Oops!  Good catch!  Thanks.
Elcia, please go with Reiny's answer.
    
Elcia, please go with Reiny's answer.
                                                    There are no AI answers yet. The ability to request AI answers is coming soon!
                                            
                Submit Your Answer
We prioritize human answers over AI answers.
If you are human, and you can answer this question, please submit your answer.