1 month ago
The
Day of Mathematics
is celebrated annually on March 14, commemorating the birthday of renowned
mathematician Pi
, born on March 14, 1879. The celebration aims to promote awareness and appreciation of
mathematics
worldwide, highlighting its importance in various aspects of life and its contributions to science, technology, engineering, and many other fields.
Events and activities organised on the Day of Mathematics often include mathematical exhibitions, lectures, workshops, competitions, and outreach programs aimed at engaging people of all ages and backgrounds with the beauty and relevance of mathematics.
On this occasion, what better way to honour the discipline than by exploring some clever mathematical tricks for quick mental calculations? From speeding up your arithmetic to impressing your friends with mathematical wizardry, mastering the below given math tricks can not only enhance your problem-solving skills but also make daily calculations a breeze.
Here are 7 clever tricks for mental math that will boost your calculation speed and make your life easier. From squaring numbers in a flash to multiplying by tricky digits, get ready to sharpen your mental math skills with these techniques!
Multiplying by 11
To multiply any two-digit number by 11, just add the two digits together and place the result between the original digits. For example, to find 11 × 23, add 2 and 3 to get 5, then place 5 between 2 and 3 to get 253.
Squaring numbers ending in 5
To square a number ending in 5, take the digit before 5, multiply it by its successor, and then append 25 to the result. For example, to find 65², take 6 and multiply it by its successor, 7, to get 42, then append 25 to get 4225.
Multiplying by 5
To multiply any number by 5 quickly, simply divide the number by 2 and then multiply by 10. For example, 37 × 5 can be calculated as (37 ÷ 2) × 10, which equals 185.
Multiplying by 9
To multiply any number by 9, simply multiply by 10 and then subtract the original number. For example, 37 × 9 can be calculated as (37 × 10) - 37, which equals 333.
Finding percentages
To find 10% of a number, just move the decimal point one place to the left. To find 1% of a number, move the decimal point two places to the left. For example, 10% of 250 is 25, and 1% of 250 is 2.5.
Finding squares near 100
To find the square of a number close to 100, subtract or add the difference between the number and 100 from/to 100, then add the square of that difference. For example, to find 96², subtract 4 (the difference between 96 and 100) from 100 to get 96, then add 4² (16) to get 9216.
Divisibility by 3
If the sum of the digits of a number is divisible by 3, then the number itself is divisible by 3. For example, 573 is divisible by 3 because 5 + 7 + 3 = 15, which is divisible by 3.
