SOLUTION: What is the percent rate per annum if $5760 interest is paid when $12800 is invested for 6 years? Show working

Algebra.Com
Question 941606: What is the percent rate per annum if $5760 interest is paid when $12800 is invested for 6 years? Show working

Answer by TimothyLamb(4379)   (Show Source): You can put this solution on YOUR website!
compound-interest formula:
v = p( 1 + (r/n) )^(nt)
where:
v = final value
p = initial (principal) value
r = interest rate (as a decimal)
n = number of compounding periods per year
t = number of years
---
5760 + 12800 = 12800*( 1 + (r/1) )^(1*6)
(5760 + 12800)/12800 = ( 1 + (r/1) )^6
( 1 + (r/1) )^6 = (5760 + 12800)/12800
( 1 + r )^6 = 1.45
---
take the 6th root of both sides:
---
1 + r = (1.45)^(1/6)
1 + r = 1.06388495429
r = 1.06388495429 - 1
r = 0.06388495429
---
answer:
6.388495429 % per annum
---
Free algebra tutoring live chat:
https://sooeet.com/chat.php?gn=algebra
---
Solve and graph linear equations:
https://sooeet.com/math/linear-equation-solver.php
---
Solve quadratic equations with quadratic formula:
https://sooeet.com/math/quadratic-formula-solver.php
---
Solve systems of linear equations up to 6-equations 6-variables:
https://sooeet.com/math/system-of-linear-equations-solver.php
---

RELATED QUESTIONS

How to calculate the rate percent per annum if $5760 interest is paid when $12800 is... (answered by Boreal)
(1) $600 invested at simple interest for 2 years earns $96. what is the rate of interest... (answered by rfer)
If money is invested for 4 years at a simple interest rate of 13.2% per annum, the... (answered by josmiceli)
9600 is invested at 8% per annum simple interest for 5 years. What is the amount of... (answered by jim_thompson5910)
Find the balance of the account after; 2 years if K3000 is invested at 8% per... (answered by Theo)
Jen invested 20000 part in bonds that paid 3% per annum and the remainder in term... (answered by Theo)
If Linda borrowed $2,100 from the bank at 9% simple interest per annum for two years what (answered by josmiceli)
If 2500 dollars invested in a bank account for 6 years, compounded quarterly, amounts to (answered by josmiceli)
What is the rate percent per annum if a sum of money doubles itself in 17 years at... (answered by josgarithmetic)