Are you prepared to improve your aptitude for mathematics? You may complete calculations more quickly using these basic arithmetic techniques. They are also helpful if you want to impress your parents, friends, or teachers.
01 of 10
Multiplying by 6
When multiplying 6 by an even integer, the result will have a single digit. Half of the number in the one’s place will be in the tens.
Example: 6 x 4 = 24.
02 of 10
The Answer Is 2
- Consider a number.
- Increase it by 3.
- Add 6.
- Subtract 3 from this value.
- Deduct the figure from Step 1 from the response from Step 4.
The answer is 2.
03 of 10
One-Digit Three-Digit Number
- Consider any three-digit number where each digit is the same. 333, 666, 777, and 999 are a few examples.
- Summarize the digits.
- Subtract the response from Step 2 from the three-digit number.
The answer is 37.
04 of 10
Six Digits Become Three
- To construct a six-digit number, write any three-digit number twice. Examples are 552552 or 371371.
- Multiply the result by 7.
- Multiply it by 11.
- Multiply it by 13.
It doesn’t matter whatever order you divide things up in!
The three-digit number is the solution.
For instance, 371371 will give you 371, while 552552 will give you 552.
- Pick any three-digit number and use the associated method.
- Add 7, 11, and 13 to it.
An outcome is a six-digit number that is a multiple of three.
Example: 456 becomes 456456.
05 of 10
The 11 Rule
This is a simple method for mentally multiplying two-digit integers by 11.
- Distinguish the two numbers in your head.
- Combine the two digits.
- Insert the second-step number between the two numbers. Put the one digit in the space and carry the ten’s digit if the number from Step 2 is more than 9.
Examples: 72 x 11 = 792.
57 x 11 = 5 _ 7, but 5 + 7 = 12, so put 2 in the space and add the 1 to the 5 to get 627
06 of 10
Memorizing Pi
How many letters are there in each syllable of the phrase “How I wish I could calculate pi”? That will help you memorize the first seven digits of pi.
They are 3.141592.
07 of 10
Contains the Digits 1, 2, 4, 5, 7, 8
- Choose a number between 1 and 6.
- Increase the amount by 9.
- Increase it by 111.
- Increase it by 1001.
- Multiply the result by 7.
The sum of the digits 1, 2, 4, 5, 7, and 8 will equal the number.
Example: The number 6 yields the answer 714285.
08 of 10
Multiply Large Numbers in Your Head
The arithmetic may be made simpler by using the distance between two double-digit values and 100:
- Deduct each value from 100.
- Summarize these figures.
- The first component of the solution is 100 minus this number.
- To get the second component of the solution, multiply the digits from Step 1.
09 of 10
Super Simple Divisibility Rules
You’re wondering whether your party can divide the 210 pizza slices equally. Use these straightforward shortcuts to do the arithmetic in your brain rather than pulling out the calculator:
- If the final digit is a multiple of 2, then it is divisible by 2 (210).
- 3 if the total of the digits is a multiple of 3 (522 because the digits add up to 9, it is divisible by 3).
- 4 if the last two digits are 4 or less (2540 because 40 is divisible by 4).
- If the final digit is 0 or 5, it is divisible by 5 (9905).
- If it meets the requirements for both 2 and 3, it is divisible by 6 (408).
- Is a multiple of 9 if the total of the digits is a multiple of 9 (6390 because 6 + 3 + 9 + 0 = 18 is a multiple of 9).
- Divisible by ten if the last digit is a 0 (8910).
- Divisible by 12 if the conditions for divisibility by 3 and 4 are met.
For instance, the 210 pizza slices may be uniformly divided into groups of 2, 3, 5, or 10.
10 of 10
Finger Multiplication Tables
You can count on your fingers; everyone can do it. Did you know that you could multiply with them? To quickly do the “9” multiplication table, extend the fingers and thumbs of both hands in front of you. Fold that number finger down, counting from the left, to multiply 9 by that number.
Examples: Fold down the fifth finger from the left to multiply 9 by 5. To get the answer, count the fingers on each side of the “fold.” The response in this instance is 45.
Fold the sixth finger downward to multiply 9 by 6, yielding a result of 54.
