i have read and tried all of the threads on calculating time difference but
none of them work.

Specifically
i have done an export of data to excell the times come out like this,
A B C
start end
2:00pm 3:50pm 1 ( i want to round this to the nearest hour)

I formated the above cells h:mm pm
and the formula cell as general with decimals

i have tried =b1-a1
=int((b1-a1)*24)

none of which work, if i delete the pm or am it will calculate, but not
accurately.

I want to round up the time calculation to the nearest number,
ie, 2:00pm 3:50pm 2(hours)

any thoughts?