Query database based on numeric value entered on an input field

I have a table listing invoices that I would like to filter based on a dollar amount that is entered on an input field. I have my query set-up with the condition “amount equals $_GET.amout”. On my webpage I have added the server connect action that has the amount variable pointed to my input field. However, the table is not being filtered when I enter any amount (which I know exists) in the input field. I use similar filtering of my tables with text inputs using “contains” conditions on my query and those work fine. Is there a different way to treat numbers with the “equal” condition?