Question 389825
on January 1, Mr. Warner and his son jointly invest a sum of money at an annual rate of 6.75%. On January 1 of the following year, their total investment is worth $5978. If Mr. Warner invested $4500 of his own money, how much money did his son invest?

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let them investtogether  $x
Warner invests 4500
Son invests x-4500
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Interest in 1 year = 5978-x
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Total investment =x
6.75x= 100*(5978-x)
6.75x=597800-100x
106.75x=597800
x=597800/106.75
They invested $ 5600.00
son invested 5600-4500 
= $1100
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m.ananth@hotmail.ca