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Via Collision Detection, I learn that actress Danica McKellar — who played Winnie Cooper on The Wonder Years and has since turned up as speechwriter Will Bailey's sister Elsie Snuffin on The West Wing — is also a mathematician. The real McCoy: she has a proof published in an academic journal.

So the charming thing is that on her website, in addition to a filmography and a few pictures and biographical information and such, she has a little section of math tutoring.

Q:
Hi Danica, I heard a question from Mr. Feenie on a Boy Meets World episode which he claimed to be unanswerable. After hearing that, I decided to figure it out. If it takes Sam 6 minutes to wash a car by himself, and it takes Brian 8 minutes to wash a car by himself, how long will it take them to wash a car together?

Danica Answers:
Hm, unanswerable? That's TV for you. :)

Let's do it: This is a “rates” problem. The key is to think about each of their “car washing rates” and not the “time” it takes them ...

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Q:
I think you are great on The West Wing! Here’s my current problem, it’s in advanced finite math (I’m a high school senior): At the height of the Beatles’ popularity, it was estimated that every popular music station played their music 40% of the time. If you tuned through 10 such stations at any given moment, what is the probability that at least one of the stations would be playing a Beatles song? Thanks!

Danica Answers:
A probability question! Okay, let’s call x the probability that “at least one of the 10 stations would be playing a Beatles song at that moment.” That’s what we’re asked to find. Then let’s call y the probability that "none of those 10 stations would be playing a Beatles song at that moment." Notice that x + y = 1 ...

Fun. And sexier than the usual actress' promotional ploy of appearing in lad magazines in lingerie.