Cube root of a perfect cube number (shortcut method)
If there is a number which is perfect cube of a number, then finding its cube root is an easy job. First of all, we should know that cube root will have number of digits equal to number of triplets, whether complete triplet or partial triplet, formed from one end of that number. So if a number has 5 digits then from one end, say right, there will be one complete triplet of 3 digits, and another one partial triplet of 2 digits, so cube root will have two digits. For example cube root of 24389, will have cube root having two digits. Let us take example of finding cube root of this number 24389. Step 1 Take last three digits 389. Consider last digit 9 of this number 389. Multiply this number 9 by itself 9, we get 81, again multiply 81 by 9. So we get a number whose unit digit number would be 9 as 9 ✖ 9 ❌ 9 = 729. So last digit is 9. Short cut 9 x 9 = 81 ×9 = ...9 as 1 of 81 multiplying to 9 will give 9. [ Some texts mentions that for the unit digit of cube root of a perfect cu...