There are a few parts of this episode that don't make sense. In the episode Larry tells a woman he had sex with that his name was Jack Tripper and he was a dentist. Sandra thinks she is pregnant and comes to the apartment looking for Jack and tells Janet and Chrissy. Jack thinks he got his girlfriend pregnant and its all a misunderstanding.
Here are some holes in the script:

Sandra finds Jack Tripper in the phone book and calls the apartment. Jack just moved in the earlier season. Unless they changed numbers how would Jack be listed in the phone book with that number for the apartment?

In the uncut version and before syndication we find out that Sandra calls Chrissy from a phone booth and Chrissy tells Sandra Jack is upstairs with his friend and gives Sandra Larry's number. Larry answers the phone and asks her how she got his number. Sandra then complains that its been weeks since Larry has called her. If Larry has called her before would she not have his number already? He liked her so much that Larry gave her a ring. That would imply they met more than once.

I usually hate threads like this because sitcoms are not reality and you cant force reality on a sitcom. I just happened to watch this the other day and found this interesting. Anyone else notice any other inconsistency with this episode?

Sandra then complains that its been weeks since Larry has called her. If Larry has called her before would she not have his number already?
I'm thinking here that Larry just never gave Sandra his number, this was the 70's so caller ID didn't exist.

As for the rest of the plot I just don't think much of it.

I'm thinking here that Larry just never gave Sandra his number, this was the 70's so caller ID didn't exist.

As for the rest of the plot I just don't think much of it.
Your comment made me go back and watch the episode. Her exact line is "how come you have never called me, not for weeks"
So my first statement cant be correct. He never did call her.

When he asks her how he got his number, she said I called the one on the phone book and they gave me this one. Larry looks at Jack and mumbles something in frustration, like how could you be so dumb to have a listed phone number.
Larry, why do you keep using Jack's name ? LOL