The answer is six.
4 seconds sound clip from the Bon Voyage, Charlie Brown movie soundboard.
You can hear this line at 00:52:09 in the Blu-ray version of the movie.
Quote context
[...]
- Ma'am? Oh, no, ma'am. I guess there was an airplane flying over or something.
- Patricia? Patricia, are you asleep?
- How many times does 25 go into 75?
- I'm awake! I'm awake! The answer is 12.
- Three.
- You contradicted me, Chuck. You made a fool out of me in front of the whole class.
- Well, six was the wrong answer. I had to say three.
- You don't like me, do you, Chuck?
- Move your elbow, Chuck. It's in my way. I can't write with your elbow in my way, Chuck.
[...]
Actors: Arrin Skelley (Charlie Brown), Annalisa Bortolin (Sally Brown), Patricia Patts (Peppermint Patty), Daniel Anderson (Linus van Pelt), Laura Planting (Lucy van Pelt)
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