bolligerallstar

it can be done with the Amort button on your calc.

Use
PV=-393750 N=360 I/Y=8/12
CPT PMT
=2889.20

2nd Amort
P1=1 Down Arrow
P2=12
BAL=390460.75
PRN=3289.25
INT=31381

P1=13
P2=24
PRN=3562.25
INT=31108

25,36
PRN=3857.92
INT=30812

37,48
4178
30492

CP