(11C) Solve for [i] given [n] [PMT] [FV]

[Gamo]

Financial program to solve for [i] the interest given Period [n], Payment [PMT] and Future Value [FV]

LBL A for [n]
LBL B for [i] (To solve for Interest)
LBL C for [PMT]
LBL E for [FV]
LBL D for Reset

This program didn't use Sign Convention when pay out show negative value.

Example:
Switch to USER mode: f USER
D > 0.00 (Reset)

180 > A > 180 (input period [n])
180 > C > 180 (input payment [PMT])
45000 > E > 45000 (input future value [FV])

B > 0.35 (answer for interest [i])

Remark: If try this example using Financial Calculator like HP-12C make sure the Payment [PMT] is negative --> -180

Program:

Code:


*LBL A    // [n]
STO 1
RTN
*LBL C    // [PMT]
STO 3
RTN
*LBL E    // [FV]
STO 5
RTN
*LBL B    // [i]
RCL 5
RCL 3
÷
STO 6
RCL 1
-
LSTx
1
-
x²
RCL 6
+
÷
2
x
0
X=Y
RTN
CLx
Rv
STO 2
*LBL 1
RCL 2
1
+
STO 6
RCL 1
Y^X
STO 7
1
-
RCL 2
÷
RCL 3
x
RCL 5
-
RCL 1
RCL 2
x
RCL 7
RCL 6
÷
x
1
+
RCL 7
-
RCL 2
x²
÷
RCL 3
x
÷
FIX 9
STO - 2
PSE
ABS
EEX
6
CHS
X≤Y
GTO 1
RCL 2
FIX 2
EEX
2
x
RTN
*LBL D
CLx
STO 1
STO 2
STO 3
STO 5
STO 6
STO 7
RTN

Gamo