HOW DID I NOT KNOW THIS?!
Why do I learn more about math from Tumblr than my 12+ years of formal education????????
No math teacher ever taught me this trick. Got damn.
This is great and all if you know how to subtract things from 100
it’s common sense to do this tho?
If so many people haven’t been taught this trick then it’s not common at all. It’s brilliant to know it now when I’m not even in school anymore.
(via no-one-sees)
