How about creating a parameter. I'll call it Values > Than and make it a type-in. Then create a calculated field:
IF [Cal 1]>=[Values > Than] THEN
Drag this to filters and only keep values of "Include"
Condition Filter_v10.5.twbx 1.4 MB
@Nancy: Perhaps I'm not understanding the question...if I make the filter pill into a continuous filter pill then the readouts can be used to type in. In this view I've clicked on the filter's menu and changed it to an "At Least" filter so users can type in values:
at least filter.twbx 1.5 MB