Texas Instruments Titanium TI-89 User Manual

Activities 770
Finding the Interest Rate of an Annuity
Finding the Interest Rate of an AnnuityFinding 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.

Texas Instruments Titanium TI-89 Specifications

General

Display Type	LCD
Display Resolution	160 x 100 pixels
Memory	188 KB RAM, 2.7 MB Flash ROM
Type	Graphing Calculator
Display	Monochrome
Processor	Motorola 68000
Processor Speed	12 MHz
Power Source	4 AAA batteries
Connectivity	USB
Programming	TI-BASIC, Assembly
Operating System	AMS (Advanced Mathematics Software)