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Interactive video lesson plan for: The 1089 rule (KristaKingMath)

Activity overview:

► My Pre-Algebra course: https://www.kristakingmath.com/prealgebra-course

The “1,089 rule” isn’t really a rule at all, it’s more like a fun thing that happens with numbers that you can explain with algebra. What it tells you is that you can pick any 3-digit number with decreasing digits, like 742 or 863, and that if you reverse the digits of that original number, and then subtract the reversed number from the original number, that you’ll get a result from that subtraction. And then if you reverse the digits of that result, and then you add the result together with the reversed result, that you’ll get 1,089 every time, no matter which 3-digit number you started with. Which, when you think about it, is pretty crazy considering that there are a whole lot of 3-digit numbers out there.

● ● ● GET EXTRA HELP ● ● ●

If you could use some extra help with your math class, then check out Krista’s website // http://www.kristakingmath.com


Hi, I’m Krista! I make math courses to keep you from banging your head against the wall. ;)

Math class was always so frustrating for me. I’d go to a class, spend hours on homework, and three days later have an “Ah-ha!” moment about how the problems worked that could have slashed my homework time in half. I’d think, “WHY didn’t my teacher just tell me this in the first place?!”

So I started tutoring to keep other people out of the same aggravating, time-sucking cycle. Since then, I’ve recorded tons of videos and written out cheat-sheet style notes and formula sheets to help every math student—from basic middle school classes to advanced college calculus—figure out what’s going on, understand the important concepts, and pass their classes, once and for all. Interested in getting help? Learn more here: http://www.kristakingmath.com

FACEBOOK // https://www.facebook.com/KristaKingMath/
TWITTER // https://twitter.com/KristaKingMath
INSTAGRAM // https://www.instagram.com/kristakingmath/
PINTEREST // https://www.pinterest.com/KristaKingMath/
GOOGLE+ // https://plus.google.com/+Integralcalc/
QUORA // https://www.quora.com/profile/Krista-King

Tagged under: 1089 rule,1089 trick,math trick,algebra trick 1089,decreasing digits,reversing digits

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