Guys dumb question, but I am having trouble with my inputs for TVM problems etc. Example, if i enter N=3 for the periods and then i hit ENTER, then I go to PV to put in 100 but it is already set on 3 from before. then if i change the PV to 100 it changes everything else. Any thoughts as to why I am not locking in my inputs? Thanks
I wonder assigning same value to two variables and reassigning the different value would change everything. What do you mean by it changes everything? Basically how it functions is the variables take the value from ANS i.e. previously entered or calculated value from memory. In fact, you can get the ANS manually as well if you like by pressing 2nd ANS Here is what you are trying now: 3 N enter PV FV. N=3, FV=1000, I/Y=10, PMT=-100, PV=? You should follow these key strokes for the above problem: 2nd clear TVM 3 N enter 1000 FV enter 10 I/Y enter 100 +/- PMT enter CPT PV
i hit “N” type in “3” and hit ENTER (that should lock in 3 right?). Then i hit “PV” to put in my PV value, but “3” is already in there. If I change that “3” in the PV to 1000, it changes my N from 3(previously) to 1000 as well. Why is it doing that?
why do you hit ENTER ? do compute the example Sgupta gave above, you just need to type each value and hit the corresponding key, no need to hit ENTER as for the calculation of the NPV or IRR or stats. Once you have input your data, just hit the CPT key then PV…and that’s it
Well I think I messed it up…yes Miss*Yiota is right…no need to enter the enter key in TVM problems…btw, you bring up a very important point here that changing your values inside variable screen changes everything. Man, I tried all odd combinations on my calculator, it doesn’t change. In fact, if you try to change after pressing PV, you will get the normal screen and it will come out of the TVM mode. Check the manual and see if your settings are messed up as I know there are so many settings on this calculator. Make sure, you follow the steps in the manual and change the settings accordingly. Its funny but even TI doesn’t recommend their own factory default settings. 
I think the problem is that you are entering N first and then 3 rather than entering 3 and then N. Likewise you should enter 100 and then PV rather than the other way around. Always type the number in first and then identify the type of variable - N, I, PV, PMT, FV. No need to use the “Enter” key.
Technically, there is nothing wrong in entering the key(N) first and then number. Just that no of key strokes will be more compared to the alternate approach wherein you enter the number first and the then press the button for variable.