Entering minutes and seconds, How?

Hello, 

I'm trying to establish a duration field and in it I would like to accurately represent minutes and seconds.

I was able to do this by creating a Numeric field [Length] where users enter in a value like 4.12 ( 4 min 12 seconds ) and in the duration field I have this Formula : Minutes([Length]).

With this - the duration field will have this value "4.12 mins". Thats ok, but I have 2 issues.

1 - How can I get the value to be 4:12 mins

2 - I noticed that sometimes the duration value will output to "4.309983333333" mins when 4.31 is entered in the Numeric field.

I might be complicating things - the must be an easier way, but #2 is my bigger issue. I need to accurately represent minutes and seconds.

Thanks!​

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Manny Pinheiro
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