Question 220818
Let  x=  amt  invested  at  8%,,,and  y=amt  invested  at  7%
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.08x +.07y = $ 479
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but,,,x+y = $ 3600,,,,or  y= 3600-x,,,,,,subst
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.08x +.07(3600-x) = 479
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.08x + 252 -.07x = 479
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.01x = 227
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x= $22,700,,,,,,y = 3600-22,700 = -19,100
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check.,,,,,.08(22700) +.07(-19100) = 479
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1816 - 1337 = 479,,ok,,,,,math  wise
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REVIEW,,his  return  was  479 /3600 = 13.3% annually
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He  could  not  make  this  return  with  only  7%  and  8% rates
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AND,,,,he  only  had  6  months  to accomplish  the  return  not  one  year
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therefore  the  rate  would  have  to  be  more  like 26.6%
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