SOLUTION: This one has me stumped on how to start. Given the formula A=p(1+r/t)^nt, answer the following problem: Find r given (A)=$95375, (p)=$65,750, and t=15 years with interest compoun

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: This one has me stumped on how to start. Given the formula A=p(1+r/t)^nt, answer the following problem: Find r given (A)=$95375, (p)=$65,750, and t=15 years with interest compoun      Log On


   

Question 111876: This one has me stumped on how to start. Given the formula A=p(1+r/t)^nt, answer the following problem: Find r given (A)=$95375, (p)=$65,750, and t=15 years with interest compounded monthly. Here's the formula I had after I plug every thing in to the formula: $95375 = $65750 (1+r/12)^(12*15 or 180)
How do I start solving for r?
Found 2 solutions by jim_thompson5910, scott8148:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
95375=65750%281%2Br%2F12%29%5E180 Start with the given equation

95375%2F65750=cross%2865750%2F65750%29%281%2Br%2F12%29%5E180 Divide both sides by 65750


1.45057034220532=%281%2Br%2F12%29%5E180 Divide


root%28180%2C1.45057034220532%29=root%28180%2C%281%2Br%2F12%29%5E180%29 Now to get rid of the exponent of 180, simply take the 180th root of both sides


root%28180%2C1.45057034220532%29=1%2Br%2F12 Simplify

1.0020685633009=1%2Br%2F12 Take the 180th root of 1.45057034220532

1.0020685633009-1=r%2F12 Subtract 1 from both sides

0.0020685633009=r%2F12 Subtract


0.0248227596108=r Multiply both sides by 12


So the interest rate is approximately 0.0248227596108, or 2.482%

Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
dividing by 65750 gives 95375/65750=(1+r/12)^180

rules of exponents gives (95375/65750)^(1/180)=1+r/12

(((95375/65750)^(1/180))-1)*(12)=r