A big math problem

[whoops1995]

Alright, so we've all seen that problem with the dogs but thats just probability. Pshhh...
I got a problem for you guys.

Part of $20,000 is invested at 12% interest. The rest is invested at 8% interest. The total interest earned from the two accounts is $1,800. How much money was invested at each rate?

 

[black lincon]

is it compound interest or simple interest, they have 2 different formulas and the answers you would get would differ based on which ones you use.

 

[whoops1995]

is it compound interest or simple interest, they have 2 different formulas and the answers you would get would differ based on which ones you use.

simple interest

 

[black lincon]

is it compound interest or simple interest, they have 2 different formulas and the answers you would get would differ based on which ones you use.

simple interest

OK then how many times has the interest been compounded?

 

[whoops1995]

is it compound interest or simple interest, they have 2 different formulas and the answers you would get would differ based on which ones you use.

simple interest

OK then how many times has the interest been compounded?

your over thinking this just think of it as a percentage

 

[black lincon]

is it compound interest or simple interest, they have 2 different formulas and the answers you would get would differ based on which ones you use.

simple interest

OK then how many times has the interest been compounded?

your over thinking this just think of it as a percentage

I'm not over thinking it your under thinking it. I'm not asking for info on how to make the problem easier I'm to ascertain all the facts that pertain to the problem. you could simply make it compound interest and not have to worry about how many times its been compounded.

 

[gamebrain89]

is it compound interest or simple interest, they have 2 different formulas and the answers you would get would differ based on which ones you use.

simple interest

OK then how many times has the interest been compounded?

your over thinking this just think of it as a percentage

He must be an accountant. We did this a few weeks ago in my accounting class, but I don't remember how right now.

 

[black lincon]

is it compound interest or simple interest, they have 2 different formulas and the answers you would get would differ based on which ones you use.

simple interest

OK then how many times has the interest been compounded?

your over thinking this just think of it as a percentage

Does this capture what you're saying:

Part of $20,000 is invested in a zero cupuon bond as 12% interest. The rest is invested in a zero cupuon bond at 8% interest. They both mature the same day. On that day...

i believe that would do it.

is it compound interest or simple interest, they have 2 different formulas and the answers you would get would differ based on which ones you use.

simple interest

OK then how many times has the interest been compounded?

your over thinking this just think of it as a percentage

He must be an accountant. We did this a few weeks ago in my accounting class, but I don't remember how right now.

no, but I'm the son of an actuary.

 

[whoops1995]

oh god my 8th grade mind is beginning to melt, hmmm alright lemme try to make this as simple as i can. Il just do the first step i guess.

1800=(X).12+(Y).08 X+Y=20,000

alright that's as far i got its up to you guys now.

 

[geizr]

Is this your homework?

 

[whoops1995]

a question, yes >.>

 

[shred_demon]

1. 1.08x + 1.12y = 21800
2. x + y = 20000
3. 1.08x + 1.08y = 21600
4. 0.04y = 200
5. y = 5000, x = 15000

 

[Zeromaxx]

5000 in .12 15000 in .08 should work out to 600 and 1200 respectively of its not specifically an accounting question...if it is I'd have to go and find an old book I have lieing around somewhere...

-ah...shred beat me to it

 

[black lincon]

a question, yes >.>

really you were trying to pawn off an eight grade math problem that you couldn't explain? if you need help with homework don't ask people who are going to question your knowledge of the subject, ask teachers for help, they tend to be less of a condescending ass than me.

 

[whoops1995]

1. 1.08x + 1.12y = 21800
2. x + y = 20000
3. 1.08x + 1.08y = 21600
4. 0.04y = 200
5. y = 5000, x = 15000

kudos on getting the right answer though can you explain how you did it?

 

[Ancalagon]

(1) x+y =20000
(2) 0.12x + 0.08y = 1800

(3) x=20000-y (from 1)
substitute 3 into 2:

0.12(20000-y) + 0.08y = 1800
(0.12 * 20000) - (0.12y) + 0.08y = 1800
2400 - 0.12y + 0.08y = 1800
2400 - 0.04y = 1800
600 - 0.04y = 0
600 = 0.04y
y = 15000
x = 5000 (from 1)

so 5000 is invested at 12% interest, and 15000 at 8% interest.

EDIT - beaten to it, but at least it didn't take 900-odd posts...

 

[whoops1995]

no, i knew the answer thats why i know shred is right(bro helped) was just seeing if you guys could get it.

EDIT: mainly becuase it didn't seem like a fair question to ask to an 8th grader so i was checking how hard it would be for you guys.

 

[shred_demon]

lol sorry dude, it's just a simultaneous equation, nothing more. Really not a "big" math question ;p

 

[shred_demon]

my workings are there :S

 

[PumpItUp]

Is this your homework?

a question, yes >.>

Shame on you for asking. Homework is to be done by yourself, or at least with some help. Asking someone else to do it for you is cheating. And shows you're either incompetent or lazy. But don't ask us to tell you which one.