Question 1162082
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0.07x + 0.04(29000-x) = 1550   dollars.


x = {{{(1550-0.04*29000)/(0.07-0.04)}}} = 13000.


<U>ANSWER</U>.  $13000 invested at 7%  and  the rest, 29000-13000 = 16000 dollars invested at 4%.


<U>CHECK</U>.  0.07*13000 + 0.04*16000 = 1550 dollars.   ! Precisely correct !
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Solved.