Question 1108100
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0.05*x + 0.07*x + 0.09*x + 0.11*x = 1440   (where x is equal amount of each of the four investments).


0.32x = 1440  ====>  x = {{{1440/0.32}}} = 4500.


4 (four) investments of $4500 each.  The total is 4 times $4500,  or  $18000.


<U>Check</U>.  (0.5 + 0.07 + 0.09 + 0.11)*4500 = 1440.   ! Correct !
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