Texas Instruments TITANIUM TI-89 User Manual
Page 770
Activities
770
Finding the Interest Rate of an Annuity
Finding the Interest Rate of an Annuity
Finding the Interest Rate of an Annuity
Finding the Interest Rate of an Annuity
Perform the following steps to find the interest rate (
i
) of an annuity where the starting
principal (
p
) is 1,000, number of compounding periods (
n
) is 6, and the future value (
s
) is
2,000.
1. On the Home screen, enter the equation
to solve for
p
.
2. Enter the equation to solve for
n
.
3. Enter the equation to solve for i using the
with operator.
solve(s=p
†
(1+i)^n,i) | s=2000
and
p=1000
and
n=6
Result: The interest rate is 12.246%.
Note:
•
To enter the “with” ( | ) operator: Í
•
Press
8 ¸ to obtain a floating-
point result.