You want to calculate the interest on $30000.00 at 6% interest per year after 20 year(s). The formula we'll use for this is the simple interest formula, or:
Where:
P is the principal amount, $30000.00. r is the interest rate, 6% per year, or in decimal form, 6/100=0.06. t is the time involved, 20....year(s) time periods. So, t is 20....year time periods. To find the simple interest, we multiply 30000 × 0.06 × 20 to get that: The interest is: $36000.00
Usually now, the interest is added onto the principal to figure some new amount after 20 year(s), or 30000.00 + 36000.00 = 66000.00. For example:
If you borrowed the $30000.00, you would now owe $66000.00 If you loaned someone $30000.00, you would now be due $66000.00 If owned something, like a $30000.00 bond, it would be worth $66000.00 now.
