Posted by Ashtyn on .
What is "mental math" and give examples. 4th grade

Math 
Ms. Sue,
Mental math is doing simple math problems in your head. For instance, to estimate 49 + 53, you need to round to 50 + 50, which equals about 100.
You can use mental math to estimate the product of two numbers  19 times 21. Round to 20 * 20 = about 400.
Another form of mental math is to listen to the teacher give a math problem with several steps, and then give the answer. Example: 1/2 of 10 + 6  2 = ? 
Math 
undrakh,
50+50=100
20 times 20=400 
Math 
undrakh,
50+50=100
20*20=400 
Math 
Sahana,
Mental Math is practically doing math in your head. That's why the word mental meaning "mind" is in Mental Math.