What is compound interest?

STEP 1 : Recall what is principal amount
https://www.qalaxia.com/viewDiscussion?messageId=5d314015df7abf6f40e96f74
STEP 2: Recall what is simple interest
https://www.qalaxia.com/viewDiscussion?messageId=5d314532df7abf6f40e96f78
Compound interest is calculated based on the principal, interest rate (APR or annual percentage rate), and the time involved:
P is the principal (the initial amount you borrow or deposit)
r is the annual rate of interest (percentage)
n is the number of years the amount is deposited or borrowed for.
A is the amount of money accumulated after n years, including interest.
When the interest is compounded once a year:
A = P(1 + r)^{n}
However, if you borrow for 5 years the formula will look like:
A = P(1 + r)^{5}
This formula applies to both money invested and money borrowed.