Question 1206260
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ou have 50000 to invest and requier an annual return of 7000. you can invest your money in bonds, 
which pay a return of 15% per year, or you can invest in a certificate of deposit which pays 7% per year. 
how much money should you invest in each to realize exactly $7000 in interest per year?
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<pre>
Let x be the amount to invest at 15% per year.

Then the rest, (50000-x) dollars, you invest at 7% per year.


x dollars at 15% generate 0.15x dollars as the interest.

(50000-x) dollars at 7% generate 0.07(50000-x) dollars as the interest.

You want two separate interests sum up to 7000 dollars

    0.15x + 0.07*(50000-x) = 7000  dollars.


Simplify this equation and find x

    0.15x + 0.07*50000 - 0.07x = 7000

     0.15x - 0.07x = 7000 - 0.07*50000

         0.08x      =    3500

             x      = {{{3500/0.08}}} = 43750.


At this point, the problem is just solved.


<U>ANSWER</U>.  $43750 should be invested at 15% and the rest 50000-43750 = 6250 dollars should be invested at 7%.
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Solved.