Operation between hours
<p>I have 2 buttons, when I click each button a timepicker comes out and return the time in the button. I have 2 text field and 1 label. In textfield 1 I put a number that will be subtracted to the difference between the time in button 1 minus the time in button 2. </p>

<p>My second text field will have a number that I will multiply by the results of the subtraction. I also have a label that will return the result. For Example:</p>

<p>in button 1 I have 6:00pm<br>
in button 2 I have 8:30pm<br>
subtracting them the results is 2.5 hours<br>
in text field 1 I have 30 minutes<br>
subtracting 30 minutes to 2.5hours will be 2 hours<br>
in text field 2 I have number 3<br>
multiplying number 3 to 2 hours I will have 6.<br>
I would like to return 6 in the label  </p>

<p>I could solve the part where I have the date picker returning the time.</p>

<p>Can anyone give me some suggestion how to solve the second part?
Thank you!</p>
