Adding time

[latex88]

I'm trying to add minutes to Now(). I was hoping to create a table that would feed to a list box. However, I'm not sure how to format the table so that the list box shows 15, 20, 25, 30..., and when I write an expression in a query of "=now() + [Forms]![FormName].[FieldName] would result the current time plus the minutes that has been chosen in the list box.

1) How should I format the field in the table that feeds the listbox?
2) What is the syntax in my query to add now() & the field chosen?

Thanks.

 

[latex88]

woud you happen to know the exact syntax. Below is what I have but I get an error message saying it's too complex. When I take out the variable, [forms]![frmMain].[LstDeliveryTime], and substitute it with just "20", it works fine.

Result: DateAdd("n",[forms]![frmMain].[LstDeliveryTime],Now())