The membership number you found on the letter was 3846, as you memorized it, and remembered the address of the Royal Falls Country Club, while pulling up to the front of it. You saw a bunch of cards parked in front of the building before parking your own car, and got out, while following the road up to the front door.
You enter, and arrive at the receptionist's desk, where you see a bunch of people get their membership cards from after they have just got mail explaining that they have joined. "Number please," the woman says, and you say the number to her, while showing her the letter you got in the mail. "Ah, a new member," she says. "Hang on." The receptionist dug into the filing cabinet, and pulled out a blank membership, wrote your number on it, and gave it to you. "Enjoy the club," she says, while you leave.