Kitten and I covered triangular numbers a couple months ago in our Competition Math for Middle School book, but I think it’s time to revisit the topic. I like the method James Tanton gives in this new video:
More Than One Way to Solve It, Again
We continue with our counting lessons — and once again, Kitten proves that she doesn’t think the same way I do. In fact, her solution is so elegant that I think she could have a future as a mathematician. After all, every aspiring novelist needs a day job, right?
If only I could get her to give up the idea that she hates math…
Permutations with Complications
How many of the possible distinct arrangements of 1-6 have 1 to the left of 2?
Happy Powers of 10 Day!
How to Understand Fraction Division
photo by Scott Robinson via flickr
A comment on my post Fraction Division — A Poem deserves a longer answer than I was able to type in the comment reply box. Whitecorp wrote:
Incidentally, this reminds me of a scene from a Japanese anime, where a young girl gets her elder sister to explain why 1/2 divided by 1/4 equals 2. The elder girl replies without skipping a heartbeat: you simply invert the 1/4 to become 4/1 and hence 1/2 times 4 equals 2.
The young one isn’t convinced, and asks how on earth it is possible to divide something by a quarter — she reasons you can cut a pie into 4 pieces, but how do you cut a pie into one quarter pieces? The elder one was at a loss, and simply told her to “accept it” and move on.
How would you explain the above in a manner which makes sense?
Sign Up for the MathCounts Club Program
The MathCounts Club Program provides enrichment activities and puzzles for 6th-8th grade math clubs within schools — and homeschool groups may join, too! Participants receive a free Club in a Box Resource Kit, which includes the Club Resource Guide, two game boards to accompany one of the meeting plans, 12 MathCounts pencils, and a MathCounts tote bag for the coach. (Apparently they had good intentions, but they didn’t follow through. My box had no tote.)
A school (or homeschool group) may choose to participate in the Club Program, the competition or both programs. Since these programs can complement each other, any school that registers for the MathCounts competition automatically gets the Club in a Box Resource Kit, too.
For more information, check out these links:
- Sample “Game and Puzzle Month” meeting plan
- Sample Silver Level Challenge problem set
- 2011-2012 MathCounts School Handbook
- MathCounts Problems of the Week
- Updated Eligibility Guidelines for Homeschools and Virtual Schools (competition program)
- Register online
How to Translate Word Problems
Hooray! The MathCounts Mini videos are back. September’s edition is all about translating word problems into algebra:
You can practice turning words into math with these MathCounts Problems of the Week.
More Than One Way to Solve It
Photo by Eirik Newth via flickr.
In a lazy, I-don’t-want-to-do-school mood, Princess Kitten was ready to stop after three math problems. We had gotten two of them correct, but the last one was counting the ways to paint a cube in black and white, and we forgot to count the solid-color options.
For my perfectionist daughter, one mistake was excuse enough to quit. She leaned her head against me as we sat together on the couch and said, “We’re done. Done, done, done.” If she could, she would have started purring — one of the most manipulative noises known to humankind. I’m a soft touch. Who can work on math when there’s a kitten to cuddle?
Still, I managed to squeeze in one more puzzle. I picked up my whiteboard marker and started writing:
DONE
DOEN
DNOE
DENO
DNEO
ONED
ODNE
The (Mathematical) Trouble with Pizza
Photo by George Parrilla via flickr.
Kitten complained that some math programs keep repeating the same kind of problems over and over, with bigger numbers: “They don’t get any harder, they just get longer. It’s boring!”
So we pulled out the Counting lessons in Competition Math for Middle School. [Highly recommended book!] Kitten doesn’t like to compete, but she enjoys learning new ideas, and Batterson’s book gives her plenty of those, well organized and clearly explained.
Today’s topic was the Fundamental Counting Principle. It was review, easy-peasy. The problems were too simple, until…
Pizzas at Mario’s come in three sizes, and you have your choice of 10 toppings to add to the pizza. You may order a pizza with any number of toppings (up to 10), including zero. How many choices of pizza are there at Mario’s?
[The book said 9 toppings, but I was skimming/paraphrasing aloud and misread.]
- Can you figure out the answer?
Having Fun with Math
Here’s another math blog for your RSS reader: Math 4 Love. Kitten laughed out loud at their One-Minute Math Video.
Be My (Math) Valentine
Just as I was looking for a creative Valentine’s craft for Kitten, this showed up in my inbox:
Xi at 360 provides step-by-step instructions, with photos:
And for more Valentine’s Day fun:
Denise Gaskins' Let's Play Math 