linear word problem # 2

MaggieSmith12345

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Joined
Oct 16, 2010
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8
you have $500,000 in an IRA at the time you retire. You have the option of investion this money in twofunds: Fund A pays 1.9% annually and Fund B pays 6.9% annually. How should you divide your money between Fund A and Fund B to produce an annual interest income of $27,000?


Alright this question seemed similar to the last question i posted so i set it up the same with two equations being

.019x + .069y = 500,000
and then x + y = 27,000 going to y = 27,000 - x

plugging that into my first equation

.019 + .069(27,000 - x) = 500,000

however when i calculate through im getting a negative answer for x
-.05x = 498,137 so x = -9,962,740

Which i know isn't right, this makes me question my co efficients for x & y , but i did try them as they were so instead of .019 and .069 i put in 1.9 and 6.9 but it still worked out to be negative..

If someone could lend a hand, it would be greatly appreciated! Thanks so much
 

mmm4444bot

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Oct 6, 2005
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MaggieSmith12345 said:
.019x + .069y = 500,000

x + y = 27,000

You transposed the given totals.

0.019x is interest earned on x dollars

0.069y is interest earned on y dollars

The sum of these two interest payments is not $500,000.

x + y is the sum of the monies invested; that's not $27,000.


When are you going to start defining your symbols x and y ?

IF you were to do that at the very beginning, maybe you would have realized that:

x + y = 500000

Write down the definition of variables in word problems!

x = amount invested at 1.9%

y = amount invested at 6.9%

Now, continue.

 

MaggieSmith12345

New member
Joined
Oct 16, 2010
Messages
8
Touche..

Thank you I appreciate the help!
 
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