Question 1151386
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            As the problem is worded,  printed,  posted and presented,  it is not complete and,  therefore,  is not fully accurate.


            To be accurate,  it should say that 


                    a)    the account is compound;

                    b)   it should say what is the compound period,   and

                    c)   does she pay at the beginning or at the end of the compound period.


            So,  I will assume that the account is compound;  the compound period is  1  month,  and she pays at the end of each month.



<pre>
Then it is a classic Ordinary Annuity saving plan. The general formula is 


    FV = {{{P*(((1+r)^n-1)/r)}}},    


where  FV is the future value of the account;  P is the monthly payment (deposit); r is the monthly percentage yield 
presented as a decimal; n is the number of deposits (= the number of years, 40, multiplied by 12, in this case).


From this formula, you get for the monthly payment 


    P = {{{FV*(r/((1+r)^n-1))}}}.     (1)


Under the given conditions, FV = $1,000,000;  r = 0.0625/12;  n = 40*12.  So, according to the formula (1), you get 
for the monthly payment 


    P = {{{1000000*(((0.0625/12))/((1+0.0625/12)^(40*12)-1))}}} = $469.07.


<U>Answer</U>.  The necessary monthly deposit value is $469.07.


Note that of projected $1,000,000 the total of her deposits will be only  40*12 times $469.07, 
i.e. 40*12*469.07 = 225,153.60 dollars. The rest is what the account will earn/accumulate in 40 years.
</pre>

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On Ordinary Annuity saving plans, &nbsp;see the lessons

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/Sequences-and-series/Ordinary-Annuity-saving-plans-and-geometric-progressions.lesson>Ordinary Annuity saving plans and geometric progressions</A>

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/Sequences-and-series/Solved-problem-on-Ordinary-Annuity-saving-plans.lesson>Solved problems on Ordinary Annuity saving plans</A>

in this site.


The lessons contain &nbsp;EVERYTHING &nbsp;you need to know about this subject, &nbsp;in clear and compact form.


When you learn from these lessons, &nbsp;you will be able to do similar calculations in semi-automatic mode.