Decimal Places

Decimal places - Is there a general consensus on how many decimals places we should follow for ALL questions or do we need to watch out the decimal places in relation to certain topics?

I followed 4 decimal places when doing CFAI EOC - but I realized that their decimal places are all over the place depending on the topic.

I have my calculator set to 9 decimals. Gets me to the near exact answer each time. I use memory keys on the HP 12c to help with the decimals rahter than typing them in each time.

In the derivatives video the guy mentioned 5 decimal places.

SFG - How do you use the memory keys to record the decimals? Feel like i spend half my time writing them out.

You gotta step your decimal game up fellas, except for SFGiant. I’m saying at least 8. What happens when you calculate the variance for a 3 asset portfolio? Those products can be extremely small.

And don’t be afraid to write something if you need to. I write down numbers even when I don’t need to, in case I mess up. That way I don’t have to key in 30 digits again, I can just pick up from where I messed up.

On the HP 12c you can use the memory storage. Bottom middle of the calculator isa STO and a RCL key. Once you get to a part of the equation you want to save, hit STO and a # key. Do this with as many items as you need (1 to 9). Then, to plug into a formula, hit RCL and then the number key corresponding to that memory item.

For instance. Say I want to go Memory 1 / Memory 2. Key strokes are as follows.

[RCL], 1, [ENTER], [RCL], 2, [/ or division symbol].

Thx SFG!!! Can’t believe I’ve had this at my finger tips the entire time and never used it. This will be insanely helpful in derivatives.

I use memory function extensively in my TI BAII Plus but this aint helping me in swap questions. CFAI solve them by rounding off till four decimal places and so my answer never matches with them! :s