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Mental math tricks
Mental math tricks

Amazing Mathematics

Mental math is a fascinating skill that can significantly enhance your ability to perform quick calculations mentally. It’s not just about solving math problems; it’s about doing so with remarkable speed and precision. In this article, we’ll delve into some mind-boggling mental math tricks for multiplication, complete with illustrative examples.

Mental Math Trick 1: Repetitive Addition

One fundamental concept behind multiplication is repetitive addition. Instead of manually adding a number multiple times, you can use this technique to arrive at the result swiftly. Let’s explore it with an example:

Example 1: 87 x 93

Traditionally, you would perform this calculation as follows:

   87
x 93
------
  261   (87 x 3)
 783   (87 x 90, shifted one position to the left)
------
8091

Now, let’s apply the repetitive addition method:

87 is 13 less than 100, and 93 is 7 less than 100.

Subtract these differences from 87 and 93:

  • 87 – 13 = 74
  • 93 – 7 = 86

Now, multiply these differences:

74 x 86 = 6376

Add this result to the original differences:

  • 6376 + 13 = 6389
  • 6389 + 7 = 6396

The final result is 6396, which matches our earlier calculation.

Mental Math Trick 2: Cross Subtraction

Cross subtraction is another ingenious method for mental multiplication. It involves subtracting one number’s difference from 100 and the other number’s difference from 100, followed by multiplying these differences. Let’s illustrate it:

Example 2: 76 x 82

Start by finding the differences from 100:

  • 76 is 24 less than 100.
  • 82 is 18 less than 100.

Now, perform cross subtraction:

  • 76 – 18 = 58
  • 82 – 24 = 58

Multiply the results of cross subtraction:

58 x 58 = 3364

In this case, 32 serves as a carry, so the final answer is (58 + 32)64 = 9064.

These mental math tricks not only save you time but also showcase your mathematical dexterity. Practice them regularly, and you’ll be amazed at how quickly you can perform complex multiplications in your head. Impress your friends, colleagues, and teachers with your newfound mental math skills!

Mental math opens up a world of possibilities for performing quick calculations effortlessly. With these mental math tricks, you’ll become a math wizard, ready to tackle multiplication problems with confidence and flair.

Mental math tricks: 1

These mental math tricks showcase the power of quick calculations and pattern recognition. By simply multiplying a sequence of numbers by 8 and adding incremental values, we create a fascinating pattern of numbers. It’s like unlocking a secret code in mathematics. Each step reveals a number that is a permutation of the original sequence, always ending with the digits from 1 to 9. These tricks not only demonstrate the beauty of numbers but also provide a fun and engaging way to sharpen mental math skills. With practice, anyone can impress others with their ability to perform these calculations in their head.

1 x 8 +1 = 9

12 x 8 + 2 = 98

123 x 8 + 3 = 987

1234 x 8 + 4 = 9876

12345 x 8 +5 = 98765

123456 x 8 + 6 = 987654

1234567 x 8 + 7 =9876543

12345678 x 8 + 8 =98765432

123456789 x 8 + 9 =987654321

Mental math tricks: 2

These fascinating equations showcase the beauty of mathematics, where a simple pattern emerges as we multiply numbers by 9. With each step, an additional digit is added to the result, forming a sequence of consecutive ones. This intriguing pattern, where the number of ones corresponds to the number of digits in the original number, highlights the elegance of mathematical relationships. It’s a captivating demonstration of how numbers can reveal hidden patterns and structures, making math a truly mesmerizing subject

1 x 9 + 2 =11

12 x 9 + 3 = 111

123 x 9 + 4 =1111

1234 x 9 +5= 11111

12345 x 9 +6=111111

123456 x9 +7 = 1111111

1234567 x 9 +8 =11111111

12345678 x 9 +9 =111111111

123456789 x 9 +10 =1111111111

Mental math tricks: 3

These incredible mental math tricks showcase the power of multiplication and addition in creating patterns. By multiplying a sequence of numbers by 9 and decrementing the second operand, we create a mesmerizing sequence. Each step reveals a number that is a permutation of the original sequence, always ending with the digits from 8 to 0. These tricks not only demonstrate the elegance of numbers but also provide an engaging way to sharpen mental math skills. With practice, you can impress others with your ability to perform these calculations in your head, unveiling the magic of math.

9 x 9 + 7 = 88

98 x 9 + 6 = 888

987 x 9 + 5 = 8888

9876 x 9 + 4 = 88888

98765 x 9 + 3 =888888

987654 x 9 + 2 =8888888

9876543 x 9 + 1 =88888888

98765432 x 9 + 0 = 888888888

Mental math tricks: 4

In these mathematical marvels, we explore the fascinating world of multiplication patterns. Starting with the simplest, 1 multiplied by 1 results in 1—a fundamental truth. However, as we progress, we encounter remarkable symmetry. Multiplying sequences of ones by themselves creates mesmerizing palindromes, numbers that read the same forwards and backwards. From 11 to 111111111, each step reveals a new level of symmetry, culminating in the astonishing 12345678987654321. These patterns not only showcase the elegance of mathematics but also serve as a captivating mental exercise for number enthusiasts.

1 x 1 = 1

11 x 11 = 121

111 x 111 = 12321

1111 x 1111 = 1234321

11111 x 11111 = 123454321

111111 x 111111 = 12345654321

1111111 x 1111111 = 1234567654321

11111111 x 11111111 = 123456787654321

111111111 x 111111111 = 12345678987654321

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About Santosh Kumar Gadagamma

I'm Santosh Gadagamma, an Experienced Software Engineer passionate about sharing knowledge in technologies like Java, C/C++, DBMS/RDBMS, Bootstrap, Big Data, Javascript, Android, Spring, Hibernate, Struts, and all levels of software design, development, deployment, and maintenance. I believe computers are essential for the world's functioning, and I'm committed to helping others learn the skills they need to succeed in tech. My website is a valuable learning tool to help you reach greater heights in your education and career, and I believe that education has no end points.

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