SOLUTION: I am doing a MATH100 online course and one of my practice test problems is causing me trouble. It is not formatted like any of the examples in my etextbook, or any of the examples

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Question 211829: I am doing a MATH100 online course and one of my practice test problems is causing me trouble. It is not formatted like any of the examples in my etextbook, or any of the examples from my instructor's video lectures. Can you please help me? The problem is worded like this:

If Mark invests $46,000 at a rate of 6%, how much more would he have to invest at 2% to get an average 3% return?
Thank you
Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website!
f Mark invests $46,000 at a rate of 6%, how much more would he have to invest at
2% to get an average 3% return?
:
Treat just like a mixture problem:
:
Let x = amt of $ to be added
:
.06(46000) + .02x = .03(x + 46000)
:
2760 + .03x = .03x + 1380
:
2760 - 1380 = .03x - .02x
:
1380 = .01x
x =
x = $138,000 has to be invested at 2%
:
:
Check solution in original equation:
.06(46000) + .02(138000) = .03(138000 + 46000)
2760 + 2760 = .03(184000)
5520 = 5520