SOLUTION: I need to find a formula to answer an investment increase word problem. I know the interest rate compounded annually and the total amount received. I need to find the original inve
Algebra.Com
Question 985541: I need to find a formula to answer an investment increase word problem. I know the interest rate compounded annually and the total amount received. I need to find the original investment amount.
Found 3 solutions by macston, stanbon, solver91311:
Answer by macston(5194) (Show Source): You can put this solution on YOUR website!
P=principal (original investment); r=interest rate (expressed as decimal); t=time(must match rate time- if rate is 5% per year, time must be in years); I=amount of interest.
.
I=Prt Can be solved for any of the variables.
P=I/rt Divide each side by rt.
r=I/Pt Divide each side by Pt.
t=I/Pr Divide each side by Pr.
.
To find original investment, P, you must know (or be able to calculate) Interest received (I), interest rate (r), and time invested (t).
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
I need to find a formula to answer an investment increase word problem. I know the interest rate compounded annually and the total amount received. I need to find the original investment amount.
----------
General Formula:: A(t)=P(1+(r/n))^(nt)
------------------------
Your Problem::
Solve for "P"
P = (A(t))/(1+(r/n))^(nt)
------------------------------
Cheers,
Stan H.
----------------
Answer by solver91311(24713) (Show Source): You can put this solution on YOUR website!
The pieces of a compound interest problem are the future value, 
, the present value, 
, the interest rate expressed as a decimal, 
, the number of compounding periods per year, 
, and the number of years, 
^^{nt})
^^{nt}})
}{n\ln\left(1\ +\ \frac{r}{n}\right)})
}{nt}}\ -\ 1\right\])
John
My calculator said it, I believe it, that settles it
RELATED QUESTIONS
I'm stuck on the following problem:
What annual interest rate compounded annually is... (answered by Theo)
I am having problems with this particular word problem, I know I use the formula : A = P (answered by solver91311)
Find the future value of an initial investment of $5,000 invested at 7% compounded... (answered by stanbon,mananth)
I need the equations to figure out
A. $30 invested at 8% compounded continuously... (answered by Alan3354)
Compound Interest formula:
A= P(1+(r/n))^nt
I have to use this formula to answer this (answered by Theo)
Use logarithms to solve the problem.
I need to find the interest rate needed for an... (answered by lwsshak3)
Please help, I am stucked at this question:
Find the interest rate needed for an... (answered by Theo,MathTherapy)
find the number of years it would take to grow an initial investment of $2,000 to a... (answered by rfer,mananth)
Hi, I need some help. I am required to show my work, and I have NO idea how to obtain an... (answered by unlockmath)