Calculating lap time splits

Hello

I am hoping to calculate lap time splits in excel. The problem is thats its not just as straight forward as cell 3- cell 2 = lap time. excel doesnt seem to understand it as a time so calculates it in 100's not in 60's for time. I have attached an example of what im trying to acheive. Excel help is telling me that i need to create a rule but this is where i get lost.

I hope someone out there can help?

james-w-bray84

Enter those numbers as times and you won't have problems:

13:26 is time (in 60's)
13,26 is number (in 100's)

thats what i did the first time but it doesnt work properly because excel doesnt understand that its in 60's (measurement of time) if you look at the attachement i am trying to calculate the diference in time between C3 and B3 and subsequently E3 and C3

I'm looking at attachemnt and you enter there 13,26. Enter it as 0:13:26 and format as mm:ss or h:mm:ss