Problema Solution

. How much more in interest will you earn if you deposit $25; 000 in a continuous

compound account compared to an account compounded monthly for 10 years?

Answer provided by our tutors

P = $25,000 is the principal or present value

t = 10 years

r = annual interest rate


- Continuous Compounding

First lets calculate the compound amount in a continuous compound account


A = P*e^(r*t)


A = 25000 e^(10r)


the interest is A - P = 25000(e^(10r) - 1)


- Compounded Monthly


A = P(1 + i)^n


m = 12 compounding period per year

i = r/m = r/12

n = t*m = 120 total number f compounding periods


A = 25000(1 + r/12)^120


the interest is A - P = 25000((1 + r/12)^120 - 1)


How much more in interest will you earn...?


lets subtract the interests that we have calculated above:


25000(e^(10r) - 1) - 25000((1 + r/12)^120 - 1) =


= 25000((e^(10r) - 1 - (1 + r/12)^120 + 1)=


= 25000(e^(10r) - (1 + r/12)^120)