Math Wiki

Compound interest

1,016pages on
this wiki
Add New Page
Talk0 Share

Compound interest is the concept of adding accumulated interest back to the principal, so that interest is earned on interest from that moment on.


  • Amount = Principal + Interest

The amount A from a certain principal P after appying compound interest at the rate of 100r% per year in t years n times is

A = P \left( 1+\frac{r}{n} \right) ^{ n t }
  • If A = amount, P = principal, r = rate percent yearly (or every fixed period) and n is the number of years (or terms of the fixed period) the interest rates for the successive fixed periods are r1%, r2%, r3% ..., then A (amount) is given by
A = P \left[ \left( 1+\frac{r_1}{100} \right) \left( 1+\frac{r_2}{100} \right) \left( 1+\frac{r_3}{100} \right) ... \right] ^{ n t }

See also

Ad blocker interference detected!

Wikia is a free-to-use site that makes money from advertising. We have a modified experience for viewers using ad blockers

Wikia is not accessible if you’ve made further modifications. Remove the custom ad blocker rule(s) and the page will load as expected.