yogi_Working With Time in Minutes Seconds And Milliseconds

                                          Google Spreadsheet   Post  #1293
Yogi Anand, D.Eng, P.E.      ANAND Enterprises LLC -- Rochester Hills MI     www.energyefficientbuild.com.   Jul 19, 2013
user Damien Austin (http://productforums.google.com/forum/?zx=vofu5btd8s4i#!category-topic/docs/spreadsheets/vv__z9i60rk)
How do I divide an amount of minutes:seconds into x amount of equal pieces of time?
 am accessing google sheets from google Chrome 28.0.1500.71 on Mac OSX 10.8.4.

If I have a time 1:30.25 (Minutes:Seconds.Milliseconds) How could I get the sheet to divide by say 4 to get four equal parts of time? 

I am timing myself and have recorded myself setting up MacBook Airs. I started with 1 and worked up to 6 at once. I want to divide the total time by the amount of computers there are. This is so I can get an idea of "Per Device" time. Setting up one at a time is a much different time than 6 at once even when the math is done per device. 

Thanks.

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