Elementary Math Problem of the Day #1....Cogs and Rotation...Challenge your kidlet and yourself.....Solved!
This is our after dinner math problem today:
courtesy of Kangaroo Math
My daughter thought that she instantly knew the answer, but was wrong. To be fair, she had never seen gears before as part of a problem. And, I had never thought about them mathematically.
I tried to draw a picture (as the small screen on my phone made it hard to explain).
The drawing was so bad, it didn't help with the explanation at all.
Then we cut out some gears (note that one has 7 spikes, one has 8, one has 6). We physically ran through the problem.
Courtesy of My Kitchen Table
We figured out the answer. To make sure she really got the concept, we explored a few more facets of the problem:
-does it matter what size the middle wheel is? (No)
-does it matter what way you turn the first wheel? (Yes)
-what would happen if the wheels were the same size? (x would land on b)
-what would happen if you turned it twice? (land on the unlabeled spike).
Did you get "a"? Good Work! GOLD STAR!!!
BeriBeri Quite Contrary * Mathimatrix * Spiky Cog * Principal of the Homeschool
Very nice, we are homeschooling our 7 year old and he is working through daily math exercises. What grade would you recommend giving this problem to my son?
I did this with my six year old and it was a bit over her head - but we had the time to follow it out to the end, and I think she got a lot from it. I'll be posting more of these - I love challenging the kidlets.
I think it was awesome and it helped me understand how to solve the problem. I look forward to seeing more .
I would get an awful headache trying to figure that one out! I actually love math, but I seem to perpetually have what is called "cog fog" cognitive fog...I will have to remember how you explained it to your daughter when my grandchildren come around asking for help
That was fun! I suggest lots and lots of number problems, patterns etc in different guises, such as geometry or levers or... cogwheels!