Maths tricks and shortcuts are the easiest and fastest ways in which you can solve mathematical problems in the upcoming Government exams. The quantitative aptitude or the numerical ability section are most commonly a part of all major tests and if a candidate can get shortcut tricks to solve this section quickly he or she may be able to score more overall in the examination.
1. Square Root
Finding the square root of a number by estimating and multiplying can be a long procedure. Given below is a simpler method to find the square root of a number:
Example: Find the square root of 2116
To find the square root of 2116:
Step 1: See the digit at one’s place. In this case, it is 6. Now, check between 1-9, the square of what all numbers have “6” at one’s place. The answer is 42 = 16 and 62 = 36
Step 2: Now check, the square of which number between 1 to 9 is closest to the first two digits of the given number. In this case, the sum of which number between 1 to 9 is closest to 21. The answer is 42 = 16 and 52 = 25
So, one number among 44, 46, 54 and 56 is the square root of 2116
Step 3: The two numbers you got in step 2, multiply each of them with the next number in the number series. That is, 4×5 = 20 and 5×6 = 30. Since 20 is a closer number to 21. The answer has to be either 46 or 44. Multiply and check your answer.
Check yourself with the below-mentioned example:
Example: What is the square root of 1024?
Solution:
Step 1: 22 = 4 and 82 = 64
Step 2: 32 = 9
Step 3: 3×4 = 12. Since 12 is greater than 10. So the square root will be 32.
2. Cube Root
Follow the steps given below to quickly find out the cube root of a number.
Example: What is the cube root of 9261
Step 1: Find the numbers between 1 to 9 whose cube is equal to the digit present at the one’s place, here it is 1. So, we get 1×1×1 = 1
Step 2: See the first digit of the number, in this case, 9. 9 lies between the cube of 2 (2×2×2=8) and (3×3×3 = 27). Since 8 is closest to 9. Cube root of 9261 is 21.
Note: To find the cube root of 5 digit number, use the first two digits instead of the first digit in step 2
Try one example by yourself to understand the trick even better:
Example: What is the cube root of 32768
Step 1: 23 = 8
Step 2: 33 = 27 and 43 = 64
Since 27 is closer to 32, the cube root of 32768 will be 32.
Follow the steps given below to quickly find out the cube root of a number.
Example: What is the cube root of 9261
Step 1: Find the numbers between 1 to 9 whose cube is equal to the digit present at the one’s place, here it is 1. So, we get 1×1×1 = 1
Step 2: See the first digit of the number, in this case, 9. 9 lies between the cube of 2 (2×2×2=8) and (3×3×3 = 27). Since 8 is closest to 9. Cube root of 9261 is 21.
Note: To find the cube root of 5 digit number, use the first two digits instead of the first digit in step 2
Try one example by yourself to understand the trick even better:
Example: What is the cube root of 32768
Step 1: 23 = 8
Step 2: 33 = 27 and 43 = 64
Since 27 is closer to 32, the cube root of 32768 will be 32.
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