You don't have to cross-multiply every time you see fraction=fraction

It's Mental Math Monday! How would you mentally calculate 62-28? Are you thinking about it as "what's the difference?" or "take away"?

30 color guard bloopers

Tonight's trick toss with Michael and Max from Blue Devils

This is one of my favorite fraction division videos I've made so far. We can make sense of fraction division if we think about it as a missing factor in a multiplication problem.

A good subtraction strategy

In a recent video, I showed that in a 3-4-5 right triangle, the radius of the inscribed circle is 1. We can generalize this: in an a-b-c right triangle, the radius of the inscribed circle is (a+b-c)/2. Here's how we know this:

New year, new me

My 15 hardest rifle tosses. Which is your favorite?

I got a viewer request to solve this system of linear equations

It's Mental Math Monday! How would you mentally calculate 112-49?

A quick way to see if a number is divisible by 4

Here's a fun puzzle: What is the sum of the 5 angles of a 5-pointed star?

How many gifts were given in the song "12 Days of Christmas"?

He's making a list He's checking it twice He didn't write the data points in increasing order so he got the median wrong.

You've heard of elf on the shelf but have you heard of

New trick toss unlocked

What's the probability of no one grabbing their own name when picking secret Santas? (Spoiler alert: e appears here!)

It's Mental Math Monday! What goes on in your head when you're mentally calculating 12×25?

New trick toss unlocked

Can we all share a fun math fact we will never use in our life but we still think is cool?

If your kid believes in Santa, let them believe in Santa. Mathematicians still believe in imaginary numbers.

You've heard of elf on the shelf but have you heard of

Which is greater: 2025²⁰²⁶ or 2026²⁰²⁵?

Look at this student's drawing of me 😭

One of the coolest math facts that I know is that the only circle that fits perfectly in a 3-4-5 right triangle has an area of pi. Here's how we can prove this.

You've heard of elf on the shelf but have you heard of

"When will I ever use this?" "How is this useful in my life?" Not everything we learn in math has to be applied. Math can be seen as an art as well.

You've heard of elf on the shelf but have you heard of

It's Mental Math Monday! How would you mentally calculate this: 75 is 30% of _____?

You've heard of elf on the shelf but have you heard of

How can we tell if a function has a hole or a vertical asymptote?

I am so excited to announce that I am now a math instructor at UCLA! Go Bruins! I didn't get a job here or anything. I'm just a math instructor physically on their campus.

Did you know we can divide across fractions? 😱

What is the weight of the dog, cat, and bunny?l

I turned my most boring math lesson into one of my most engaging math lessons by doing this one thing

Here's a good real world math problem: Would you rather get $1,000,000 upfront, or $1,000 weekly payments for the rest of your life?

I'm telling my students this is a box and whisker plot

Why does the Pythagorean theorem work? Here are three proofs, including a proof submitted by a U.S. president 5 years before his presidency.

It's Mental Math Monday! How would you mentally calculate 95% of $300?

I asked some math educators what their response is when someone says "I hate math" and here are their responses:

Thank you, CMC North! I had a fun time sharing the math behind the tricks with you all.

Did you know all prime numbers (besides 2 and 3) are all one away from a multiple of 6? Here's how we can show this.

Why does e^ln(x)=x?

Baby names for music lovers: Melody Harmony Aria Reed Cadence Baby names for math lovers: Hexagonal Prism Intermediate Value Theorem Axis of Rotation Scalene Triangle Corresponding Parts of Congruent Triangles are Congruent

How many positive factors does 20²⁵ have?

ln|x|??? How did you get in there? 😱

If it takes Elmo 6 minutes to build a snowman and Rocco 7 minutes to build a snowman, how fast can they build a snowman if they worked together?

Why do we flip the inequality sign when we multiply or divide by -1?

If anyone has an extra holiday card, I would absolutely love one, even if we have never chatted. Howie Hua PO Box 28003 Fresno, CA 93729