Anyone that can help me out on this one please? An investor invested a total of $1,100 in two mutual funds. One fund earned a 7% profit while the other earned a 3% profit. If the investor’s total profit was $61, how much was invested in each mutual fund? The amount that was invested in the mutual fund that earned 7% was? The amount that was invested in the mutual fund that earned 3% was?
u have a linear system to solve: x for the investment in fund 1, y for ... in fund 2 then \[ \large \begin{cases} x+y=1100\\ 0.07x+0.03y=61 \end{cases} \]
I am a beginner and have no idea what i'm doing, could you explain the steps?
ok. but do u understand the equations? first that!!
Yes, I see how you have them set up, and I think i'm supposed to start with the first one and isolate x first? but I am unsure of what i am doing as a whole. I would appreciate any help.
well first, to get rid of of the decimal numbers u can multiply the 2nd equation by 100 and get \[ \large 7x+3y=6100 \] ok?
ok
now isolate x or y (your pick) from the 1st equation. what do u get?
hello! @teenandtoddlermom
I am here...I am trying to configure it, but I am unsure.
for instance you would get \[ \large x=1100-y \] right?
yes
now u can plug this into the second equation.and get \[ \large 6100=7x+3y=7(1100-y)+3y \] right?
yes. I am taking notes on what you are explaining.
can u do the algebra on this last equation: \[ \large 6100=7(1100-y)+3y \] ? post what u get
ok so ... 7(1100-y)+3 7700-y+3 7700y-3 am I on the right track?
no
:(
u didn't distribute the 7 properly
let's see: \[ \large 6100=7(1100-y)+3y=7700-7y+3y=7700-4y \] do u see where your mistake is?
so we now have \[ \large 6100-7700=-4y \] \[ \large -1600=-4y \] \[ \large y=\frac{-1600}{-4}=400 \] got it?
so that is for my first equation? you plugged it into the second equation?
now plug this into the first equation and find the value of x. try it!! it is easy
so for the x + y =1100 it's 400=1100
do I subtract them?
or its, x+400=1100?
what happened with the x?
i mean u now know y=400 so \[ \large 1100=x+y=x+400 \]
so x=700
yes.
7% = 700 and 3% is 400 is this right?
no.
x=700 (what u invest in the 1st fund) y=400 (what u invest in the 2nd fund)
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