What is "mental math" and give examples. 4th grade

Answer 1

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 = ?

Answer 2

50+50=100
20 times 20=400

Answer 3

50+50=100
20*20=400

Answer 4

Mental Math is practically doing math in your head. That's why the word mental meaning "mind" is in Mental Math.