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Glad we could make your day John. Though we wouldn't categorize this type of solution as a secret!

We recommend watching again and paying close attention to Kim's instructions.

You're never too old or too young to learn something new! Playback the video and watch Kim's explanation carefully.

Love that we could show you a different way of doing things. That's the beautiful thing about mathematics -- so many ways to reach a solution!

@@SpiritofMathSchools I'm of the age where calculators were in school bags but slide rules were at home. You think differently when you learn or have to make good estimations, and not depend on technology. Kids should still learn first on slide rules.

@@guessundheit6494 100%. There's definitely a difference in their thinking when they have to do the work! They become conditioned not to look for shortcuts in mathematics and really, in life.

We'd counterargue that learning the process behind the math is never a waste of time. Math is in our daily lives, even if it isn't always in the form of square roots. Calculators are nice to have, but relying too heavily on them weakens our math muscles.

The proof is in the video. We suggest trying it out in your own life and seeing how you it works for you

It's so wonderful to read comments like these! People looking for a long time for something they remember (like a song, recipe, or this, or something else), and it emerges for them from the Internet!

Happy to help reel in those (almost) lost memories!

@@alittax One of the many reasons we love being able to share these videos online to people around the globe! Well said.

The first 8 in 88 comes from finding what squared number goes into but not over the first pair of digits (23). 5 squared would be 25, which is over 23, but 4 squared is 16 which is as close as we can get. When you move down to the next line, you have to double that 4 (from 4 squared), which is 8. The second digit comes from looking at the number from the next row (776). You need to find what 2-digit number that starts with 8 and multiplied by the same single digit number equals close to but not over 776. If we use 9 for example, 9 x 89 = 801. If we try 8, 8 x 88 = 704. This is as close as we can get, meaning an 8 goes above 76 and 88 goes to the left, just under 776. Hope this helped!

It's never too late to learn a new approach!

Happy to help provide you with a blast from the past!

The method clearly has an international reach

Even my dog could push the square root button on a calculator if I would train him to push that particular button that has the square root symbol printed on it. Would it mean he understands advanced mathematics for any high standard? Nope.

sedqialbaik.blogspot.com/2006/04/blog-post_114434901914567834.html

The Cube Root: A Practical Method to Find It from Any Number The Cube Root A Practical Method to Find It from Any Number Sidqi Mohammed Al-Baik In the Abbasid era, Arabs excelled in mathematics, enriching the facts of arithmetic, establishing algebra and logarithms, dealing with exponents (powers) and roots, and organizing tables. It is not unlikely that they devised practical methods to find the square root or cube root, other than the method of prime factorization, but these were not known to modern mathematics scholars or were not published. However, students following the French curriculum recently learned a practical method to find the square root (as in Syria and Lebanon) while those who studied according to the English curriculum did not. I have not come across a practical method to find the cube root, nor have I found any mathematics specialists who know a practical method for the cube root. Therefore, I worked hard and for a long time, spanning several years, fluctuating between despair and hope, until I discovered this practical method to find the cube root of any large number, other than the prime factorization method. Many may now find it unnecessary to use this method and others by using calculators, which also spared them from many calculations. However, people, especially students, still need to learn different methods. This method may be an intellectual effort added to other mathematical information and facts. Here is this method, which requires knowing the cubes of small numbers from one to nine, which are (1, 8, 27, 64, 125, 216, 343, 512, 729). Method and Steps Divide the number into groups of three digits, starting from the right, after writing the number in the correct format. Start the first stage with the leftmost group, approximate its cube root, and place it above the group. Place the cube of this number under the leftmost group and subtract it. Bring down the second group next to the previous subtraction result and start the second stage. Prepare the root factor according to the following steps in the left section: A. Square the root obtained in the first stage and place a zero before it. B. Mentally divide the number obtained in step (4) by three times the squared root (from step A) by underestimating, and assume this result as the second digit of the root and place it above the second group. C. Multiply this assumed number by the previously obtained root with a zero before it. D. Add steps A and C. E. Multiply this sum by three. F. Add the previous multiplication result to the square of the assumed number. G. Multiply the sum in step (F) by the assumed number, place the product under the number obtained from bringing down the group (step 4), and subtract it. Bring down the third group to the right of the previous subtraction result, start the third stage, and repeat the steps in (5) as follows: A. Square the previous root (both digits) with a zero before it. B. Mentally divide the number obtained from bringing down the group (in step 6) by three times the squared root (from step A). C. Multiply the assumed number (from step B) by both digits of the root with zeros before them. D. Add steps (A) and (C). E. Multiply this sum by three. F. Add the previous multiplication result to the square of the assumed number. G. Multiply the previous sum (from step F) by the assumed number, place the product under the number obtained from bringing down the group (step 6), and subtract it. Continue this process. If a remainder remains after subtraction and no groups are left, add a group of three zeros and repeat the previous steps, placing a decimal point in the root as the result will have decimal parts. Practical Example Cube Root of (77854483) Divide the number: 7 2 4 77,854,483 Approximate the cube root: The approximate cube root of 77 is 4, place 4 above the first group. Subtract the cube: The cube of 4 is 64, place it under the first group and subtract it. 77 - 64 = 13 Bring down the second group: Bring down the second group: 13,854 Prepare the factor: Square the root with a zero before it: 40 × 40 = 1600 Mentally divide 13,854 by 1600 × 3 = 2 approximately Multiply 2 by 40: 2 × 40 = 80 Add 1600 and 80: 1680 Multiply 1680 by 3: 1680 × 3 = 5040 Add the square of the assumed number: 5040 + 4 = 5044 Multiply 5044 by 2: 5044 × 2 = 10,088 Subtract 10,088 from 13,854: 13,854 - 10,088 = 3,766 Bring down the third group: Bring down the third group: 3,766,483 Repeat the previous steps: Another Example: Cube Root of (12895213625) Divide the number: 5 4 3 2 12,895,213,625 Approximate the cube root: The approximate cube root of 12 is 2. Subtract the cube: The cube of 2 is 8, place it under the first group and subtract it. 12 - 8 = 4 Bring down the second group: Bring down the second group: 4,895 Prepare the factor: Square the root with a zero before it: 20 × 20 = 400 Mentally divide 4,895 by 400 × 3 = 1 approximately Multiply 1 by 20: 1 × 20 = 20 Add 400 and 20: 420 Multiply 420 by 3: 420 × 3 = 1,260 Add the square of the assumed number: 1,260 + 1 = 1,261 Multiply 1,261 by 1: 1,261 × 1 = 1,261 Subtract 1,261 from 4,895: 4,895 - 1,261 = 3,634 Bring down the third group: Bring down the third group: 3,634,213 Repeat the previous steps.

try stretching your brain doing the method for cube roots No one taught this in grades 1 thru 12. But I got interested on my own When the stress closes in, I often find myself evolving the cube root of a number looks like you are about 5 to 10 years older than I

An over-reliance on calculators makes your math muscles weak. We always encourage our students to learn the core concepts and do the arithmetic mentally or by hand whenever possible

​@@SpiritofMathSchools I tend to agree. Teachers can choose values that can be computed in the head or simple multiplication and long division on paper. Real world math rarely has those convenient numbers. Calculators, I would argue do not make one's math weak as doing the calculations is only the lowest skill on the math "tree." Knowing how to set up the problem is where the math skills shine. I suspect that those who do real world math will rarely use hand calculations, and they will quickly notice when their calculator have given faulty inputs. It is important that students learn the basic arithmetical calculation techniques and practice them in the classroom.

Unfortunately, children aren't taught this approach in grade school today and they should be!

People underestimate muscle memory, especially when it comes to mathematics! That's part of our approach with our students that we notice makes such a difference.

This method is based on Binomial Expansion (a+b)squared method. It is very easy. I can show you in a few minutes.

This method is based on Binomial Expansion (a+b)squared method. It is very easy. i can show you in a few minutes. This teacher makes it look longer than it really is.

Is there anything else you wish you saw earlier? We can help share another video for you.

Lucky for you @3Cr15w311 made a comment earlier.

Same. Never any explanation or real world examples. Just dreary rote practice out of the textbook.

We're sorry to hear that! We find the best way to learn is in a collaborative, group setting