Speed Mental Math Exercise #shorts

This was a trend on IG/TikTok, people would write out how they solved this problem. It shows that there are many ways to solve a math problem, but let me show you a faster way than stacking and adding.

This is an easy problem to teach children to group numbers to add faster.
You will start writing this out, and after practicing for a few days or weeks the child will be able to do it in their head. The top kids in the top countries for math can do this in a fraction of a second! It's always my goal to have our kids be competitive on a global scale while also having fun while learning.

Age level: any age

Prior Knowledge: The child should know common ways to make 10 ( 0+10, 1+9, 2+8, 3+7, 4+6). The child should know how to add multiples of 10 (For example 40 + 20 or 80 + 50).

93 + 97 = 190

Tell the child:
-- Is it easier to add 17 + 24 or 10 + 20? Why?
-- That's right, it's easy to add numbers that end with 0!
-- So we're always going to try to group numbers that make a 10.
-- Do you see any ways to make 10 in our problem?
-- 7 + 3 = 10
-- So now, let's rewrite our problem to make it easier to solve
-- I'm writing 90 + 90 + 10 [Write]
-- We took out the 7 and 3, and made a ten. [Point to the numbers as you say this]
-- Now, do you see any ways to make 100? [You may remind students that 100 is also "a ten"]
- That's right! We can add the 90 + 10 first, because we know that equals 100.
[Note: It's ok if the child wants to add 90 + 90 first! Whatever method is fastest for them]
- Now let's rewrite our problem again to make it easier to solve
- I'm writing 90 + 100
- Wow, it's so easy to add a number to 100! What's the answer?
- 190

Here are some other problems that you can practice with. Remember, it will be slow at first, and it's okay to use physical models.

12 + 48
33 + 67
55 + 15
81 + 49

Yes there's a lot of prior knowledge that goes into this! If this hits 2000 likes I'll make videos on those mini lessons.

[kathykickingwoman]

I taught my daughter how to do this in elementary school....she came home crying one day because everyone of her homework assignments that she used this way on....teacher gave her an F because she didn't use his formula....he also told her something like "don't take math lessons from your mom, it's obvious she didn't graduate..." even though she had every answer right and showed her work....he still gave her an F on her homework....I chewed him out and told him not only did I graduate high school....I also graduated from college and worked as a Real Estate Appraiser for 12 years and a tax assessor and a CPA....but he called me dumb...haha for over 20 years I crunched numbers every damn day...

[donnaclark]

Love it! In my head I went 9+9=18 (add a 0) 3+7=10
Total, 180+10= 190

[moose_my_beloved]

i really said 110 with so much confidence💀

[leeminhosairfryer]

i said 200 with so much confidence lmao

[indboonies]

90 plus 90 equals 180 and 3 plus 7 equals 10
10+180=190

[plantingseeds]

Can we please get more of this on the internet, so tired of seeing ppl teaching their kids how to shake their back side.

[GG-lpex]

I believe a better approach is to say the 3 takes 97 to 100, we’re left with 90+100

[reminderIknows]

my normal strategy is 90 + 90 = 180
3 + 7 = 10
180 + 10 = 190
but thats more advanced
this strategy also workss

[SuperKvlogs]

Awesome!! I did it this way, 90 + 90 = 180 and then (7+3=10) so 180 + 10 = 190

[TheCoCoBully]

Did something like this with my eight year old because he is always asking me math questions and was SO impressed by how fast and how silent he was in getting the answer! He didn’t use his fingers he didn’t write anything down he just thought about it and worked it out in his head.
All I could do was gasp and tell him how proud I was/am. Honestly didn’t think he would get due to the lack of finger counting or the lack of asking for a sheet of paper to work it out. That’s what I’m used to. Impressed by your little ones is just the beginning.

[VoiderStar]

My trick is the bigger number should be rounded to the nearest 100 for example

93 + 97 (nearest 10 power number is 100) so,
93+100 =193
And the difference between 100 -97 is 3 so
193 -3 = 190

[yvettelouise]

Love the little pose when she finished!!!

[RoliePolee]

I just have to say I’m 30 years old and I have no clue how she just added that up !! You are my inspiration haha so awesome 🙌🏽👌🏽👌🏽so happy there is a description I can read

[a_music]

Figured out how to do this in kindergarten, and am still using it daily as a freshman👍

[OkayIn]

I was one of those kids who needed to know the why behind everything. If I asked, “Why do I have to ‘carry’ the 1?” I was told over and over, “Because that’s the rule.” Fast forward to my Math for Elementary Teachers class in college, and I finally learned the method you showed here. Suddenly, all those years of mystifying math made sense! Still, many of my students’ parents hated this way of thinking because they wanted their children to learn math the “old school” way. I’m glad to see that there are parents here willing to try new things!

[LegoAndrew]

As soon as I saw the question I said “190”

[operaguy]

She's got the light of intelligence in her eyes.

[mellads]

I added it in my head got the same answer but I didn't do it that way. Where did the 90 + 10 come from?

[alanaur]

so i did this:
1
93
+97
---
190

[LUISGOMEZ-bjuc]

Intelligent young lady, well done, Great job....