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Date time calculation
Asked by labman3 on November 03, 2016 at 01:24 PMI'm trying to calculate the number of hours worked on a completed work request. I used the calculations found in the forum, but it's not accurate. i.e. if i enter START time as: 11/2/2016 at 2:10pm and the END time as: 11/2/2016 at 9:30pm, the value returned is 7.33hrs, but it should be 7.2hrs.
https://www.jotform.com/?formID=62984942194166
date time JotForm calculations www and 
JotForm Support
Hello, the calculation is correct. In 1 hour, there's a total of 60 minutes, thus 6 iterations of 10minute stepping.
The first 10 min mark is equivalent to 1/6, which is equal to 0.1666666666666667 (rounded off to .17). Then 2/6, 3/6 and so on.
Here's the complete breakdown of each 10 minute stepping:
10 mins = .17 (1/6)
20 mins = .33 (2/6)
30 mins = .5 (3/6)
40 mins = .67 4/6)
50 mins = .83 (5/6)
60 mins = 1 (6/6)
So, 9:30pm  2:10pm = 7.33
If we'll convert .33 to minutes it will be:
2 / 6 = 0.3333333333333333
0.3333333333333333 * 60 = 20 mins

how would i calculate the so the time is 7hrs 20min?

JotForm Support
Feature/optionwise, no there's no way to achieve that. But I'm currently looking for a workaround.
I can probably use Conditions to achieve something similar so allow me some time to come up with something. I'll get back to you on this same thread. :)

JotForm Support
All right, can you check my test form: https://form.jotform.com/63077719135965
Here are all the things I did:
1. I hid your Hours form calculation and named it Hours (Temp).
2. I added 2 Textboxes (1 for Hours and 1 for Minutes)
3. I used the floor() function to round off the Hours (Temp) value then push the whole number to the Hours Textbox.
4. Then I setup the conditions for each of the results of the 10minute stepping (.17 for 10 min, .33 for 20 mins, and so on).
RESULT:
You can also clone my form if you wanted to see how it was setup, here's how.
Let me know if that works for you :)

it works!! thank you very much.
