Richard Dusold

Math teacher.
"Whatever is true, honorable, just, pure, lovely, or commendable -- if anything is excellent or praiseworthy -- 𝘁𝗵𝗶𝗻𝗸 about these things."

[Richard Dusold @richard_dusold]

@TheStatsMedic I've got three days to cover Random Variables before we start to review for the exam . . . any suggestions for what I should focus on?

[Richard Dusold @richard_dusold]

@MrKitMath @BurdessAlicia @pgliljedahl @wheeler_laura 's website might be of use to you.

https://t.co/woKdX9pInh

[Richard Dusold @richard_dusold]

@BurdessAlicia @pgliljedahl These problems are amazing! Thanks so much for putting in the work to create this.

[Richard Dusold @richard_dusold]

@howie_hua From an angry parent:

"I thought you would want to learn more and take extra time to make a difference in this girl's life. That's the reason many people go into teaching and I had hoped that would apply to you as well."

You're right, actually, I'm in it for the money.

[Richard Dusold @richard_dusold]

@JennBinis @MichaelCRalph I don't see you contributing to this discussion as "rude" at all! Thanks for your thoughts - those questions are a helpful way to talk about actual issues, not just this ambiguous "factory model".

How would you respond differently if the person speaking was Black?

[Richard Dusold @richard_dusold]

@MichaelCRalph Do you have any recommended reading for a counter-narrative? The factory model is a myth, so how should we frame education?

Basically, what would you /want/ to say to the people you mentioned in your first tweet?

[Richard Dusold @richard_dusold]

@SouleSharon @therealjrbrown @pgliljedahl Let me know if you get a good strategy for teaching it . . . my kids kept getting stuck after the first payment and I couldn't get them moving forward.

[Richard Dusold @richard_dusold]

@therealjrbrown @pgliljedahl So, worked through this problem with my students today and realized I was wrong!

On day 3, you can't pay with two connected, because he's just charging you for the night's stay, not a cut. So you have to change your strategy . . .

This really is a great problem.

[Richard Dusold @richard_dusold]

@therealjrbrown @pgliljedahl Day 1 - pay with 2 connected (47)
Day 2 - pay with 4 connected and get two connected as change (42 + 2)
Day 3 - pay with 2 connected (42)
Day 4 - pay with 6 connected and get 4 connected as change (35 + 4)
Day 5 - pay with 4 connected...

How about that? Does that make sense?

[Richard Dusold @richard_dusold]

@therealjrbrown @pgliljedahl Well, I'll admit that I could have been doing the problem wrong. I looked at it as if I were using currency - paying him with a 2 dollar bill the first day, then a four dollar bill the second day, etc.

[Richard Dusold @richard_dusold]

@therealjrbrown @pgliljedahl If you pay with two connected links, you can expect to receive those two links (still connected) as change.

[Richard Dusold @richard_dusold]

@CmonMattTHINK @Dean_of_math @Mathgarden Yep! Exactly as you were saying. My way of solving it (originally) was wrong

[Richard Dusold @richard_dusold]

@CmonMattTHINK @Dean_of_math @Mathgarden This is why I barely passed my probability class . . . Here's me writing out that problem. 8/20 ways to get red one by one, 4/10 ways to get red two at a time.

You can't just combine the two probabilities because there's a chance that you get chosen first.

[Richard Dusold @richard_dusold]

@CmonMattTHINK @Dean_of_math @Mathgarden This is a question that I don't know the answer to. Curious what you think.

Let's say I have a bag of five marbles, all different colors. Does the probability of me picking a particular marble change if I pick two out at once vs. picking them out one at a time?

[Richard Dusold @richard_dusold]

@CmonMattTHINK @Dean_of_math @Mathgarden So it depends on how they select the winner! I was imagining that a radio show would do something similar to drawing names out of a hat.

How would you implement your method practically? Are you envisioning some type of program that could select winners simultaneously?

[Richard Dusold @richard_dusold]

@CmonMattTHINK @Dean_of_math @Mathgarden Quick thought:

Let's say there are 100 classrooms. If they choose one at random, you have a 1/100 (1%) chance.

If they choose a second, you have a 1/99 (1.01%) chance.

So, unless I'm missing something, you have a 2.01% chance of winning (slightly better than double!).

[Richard Dusold @richard_dusold]

@Willmdunn Students working together is one of the most important things about school.

[Richard Dusold @richard_dusold]

@NeleighJ What does next year hold for you?

[Richard Dusold @richard_dusold]

@PlateauUkok @JeremyTate41 Is it not worth studying the classics if they're not in their original language?