Hours to number conversion + IF Function ends with #Value.

Hello.
Sorry, from an infrequent Excel user, for asking a question that has no doubt been answered many times before.
I am trying to calculate daily / weekly pay with the added twist of overtime to be paid after so many hours have been worked.
I have set up my spreadsheet with -
A1-A6 - Start time Mon to Sat
B1-B6 - End time Mon to Sat
C1-C6 - Total hours worked
D1-D5 - = Hrs * hourly rate (=C1*10.25)
D6 - I have an IF function as follows =IF(D10:D14<=50,D15*10.25,D15*10.25*1.5)
I have done this as overtime is paid for Saturday, if more than 50 hours is worked Monday to Friday.
But I keep getting a #VALUE error in D6. I have tried changing format of cells for C & D columns and tried finding answers from previous threads, but to no end. If someone has an answwer for me, it would be greatly appreciated.

Thanks
Roly.

Roly, your formula makes no sense as it's referring to cells that you do not explain the contents of. I.e. d10:d14 and D15.

Could you post a sample workbook?

Thank you so much. That's the missing link. You folk are awesome.

Sorry. Cut and pasted formula directly from my worksheet without tidying it up to match my example. But it has been sorted. Thanks anyway.