sharepoint - How to do date and time comparision with a calculated date time value -

can check if date , time field less 15 minutes smaller or equal current date , time in workflow condition?

for example, if value 5:40 pm, have check if current date , time smaller 5:25 pm condition. how can do?

in sharepoint designer:

create local variable. type must date/time.

set it's value relevant date.

now, next thing use add time date function (type "time" , choose first option (at least that's position in sharepoint designer 2010, i'm using). add 15 minutes variable.

now create local date/time variable, set current date , compare both.