Find number abc

A carpet layer had just finished installing carpet for a lady. He stepped out for a smoke, only to realize he'd lost his cigarettes. In the middle of the room, under the carpet, was a bump. "No sense pulling up the entire floor for one pack of smokes," he said to himself. He proceeded to get out his hammer and flattened the hump.
As he was cleaning up, the lady came in. "Here," she said, handing him his pack of cigarettes. "I found them in the hallway." "Now," she said, "if only I could find my gerbil."