Round one number to the nearest ten to make it "friendly," solve the problem, and then adjust. Example: For 38 + 25 , turn 38 into 40 (by adding 2). The Math: . Now, take away that extra 2 you added earlier.
Give the kid the "trick" and give yourself a calculator. Race to see who gets the answer first. (Let them win!)
Cut one number in half and double the other. The answer stays the same. Example: 14 x 5 Half of 14 is 7. Double of 5 is 10. . (Much easier than 14 x 5!)
Take the first digit and multiply it by the "next" number up. 65 x 65 The end is 25 . The first digit is 6. The next number up is 7. Put them together: 4,225 . How to Make it "Irresistible"
Standard school math teaches kids to work right-to-left (ones, then tens). Mental math is much faster . The Trick: Add the "big" values first. Example: 64 + 28 Add the tens: Add the ones:
It’s great for any problem involving a 5 or an even number. 4. "Front-End" Addition