Conversion of Time Range into Minutes
Date: 11/13/2002 at 17:24:03 From: David Bird Subject: Conversion of time range into minutes Hello, I'm currently relieving a position that contains a quality improvement role. One report is related to utilisation of time, requiring me to report on 'time available' and 'actual time used' within operating theatres. Let's say the "time available" is from 0830 (start) until 1600 (finish), and the "time used" is 0835 - 1704. What equation/conversion can I use to find the number of minutes between the start and end times for both 'available' and 'actual' time on a 24-hour clock? Having an equation/conversion would save literally hours of currently manual calculations. Regards, David.
Date: 11/14/2002 at 23:10:36 From: Doctor Ian Subject: Re: Conversion of time range into minutes Hi David, I'm not entirely sure I understand what you're asking. To avoid doing the calculations 'manually', do you intend to program a computer or spreadsheet to do the calculations? A spreadsheet like Excel or the equivalent can subtract times directly. To subtract by hand, there are two cases. First, the number of minutes in the end time is greater than in the start time. In this case, you can just subtract the times as if they were integers: 1744 - 0835 ------ 909 The second case is _not_ like this: 1704 - 0835 ------ ???? In this case, you can still do something like an integer subtraction, instead of borrowing a 1 from the third column (which would represent 100 minutes), you borrow a 6 (which represents 60 minutes): 6 6 | 17 04 - 08 35 ------- 8 29 ^ ^ | | | +------ this is (60+4) minus 35 | +--------- this is (17-1) minus 8 That's really the only difference. If the interval spans midnight, you can borrow 24 hours, 24 1 6 | 02 04 - 16 35 ------- 9 29 ^ ^ | | | +------ this is (60+4) minus 35 | +--------- this is (2-1+24) minus 16 Does this help? - Doctor Ian, The Math Forum http://mathforum.org/dr.math/
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