Brennen's Brain

The kids are taking standardized tests this week at school, the Metropolitan Achievement Test or MAT 8. We have to make sure that the kids have plenty of rest and a good breakfast so that they can concentrate during testing.

Today I surprised the kids at school by bringing them a special lunch. Brennen loves Subway subs and Maeve had a quesadilla from Chipotle. As we were eating lunch together, Brennen announces to me that he has thought of a new math theory. Now, I'm not sure it this constitutes a "theory" and I'm sure it's not "new" either however, it is new to Brennen. Here it is:

If you take any two numbers that are next to each other on the number line (e.g. 4 & 5), then multiply those numbers by the same number -- the difference of the products will equal the number that you used to multiply with!

Here, let me show you an example:

We will use the number 4 & 5.
Multiply each by 7.
The answers are 28 & 35.
The difference between those is 7 (35 - 28 = 7).

Try it! I think it works with any number. Now, I can't tell you how this is actually useful but Brennen claimed to use it during his MAT 8 testing today. I'm just amazed at how that kid's brain works! He can keep coming up with as many math "theories" as he wants to.