More than likely the first mental math used was during prehistory, as there was no written language or number system.
Mental math is basically math in your head so for example 40x2=80 so I did that in my head
13.48 - 6.1 in mental math = 7.380000000000001
how to do mental math useing propertys
mental math is doing the math in your head or in your mind but not in a calculator or pencil and paper
50 what's "mental math" supposed to mean? if it just means you did it in your head, then there is no difference between mental and regular math, except that it is harder to check your work.
math that is done in your head
Mental Math Mostly
Mental MAth or Scrap Paper
No ,doing math in your head is called mental math ;which is only used if you were to be skip counting or any other thing's hopefully i answered it pretty good.
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This is math you can do in your head (mental math).13
Mental math! aka in ur head