WARNING: April 1st is coming up quickly and I want to make sure you're ready. Nobody's going to pull a fast one on you, right?
So here's a challenge:
Pick any number
Multiply that number by 4
Subtract 8 from that number
Divide that number by 4
Add 6 to that number
Subtract that number by your original number.
What did you get?
Did you get 9?
That was fun! But wait, how did I guess your number? What I did was build an algebraic expression, then I had you complete it, step by step.
For anyone looking at the problem first, it seems daunting. However, going step-by-step through the problem, it becomes more manageable. The end goal here is to make sure you end up with a last step like I did, such as:
That way, you know your original number will subtract to zero and you are left with a specific value. That is how I knew you ended with 9!
For younger kids, you might try something simpler:
Pick a number (not a zillion... something you can count to!)
Add 3 to your number
Add 2 to that number
Subtract your original number from your new number
You should have 5!
So here's my bigger challenge to you. Create one with your child, or with your class of students, and send it to me. I'm going to take a few of them and feature them on the website, tabletalkmath.com, and will be giving out a special prize to a few of my super-puzzlers. Challenge me!
If you have any questions, please feel free to contact me on Twitter (@TableTalkMath) or comment below. Be sure to have your friends sign up for the newsletter at tabletalkmath.com for weekly updates.
Thank you for taking the time to improve math fluency for children, one table talk conversation at a time.