To find cube root of a cubic numbers:

What are cubic numbers

cube of 1= 1, (ends with 1),cube of 11= 1331 (ends with 1), and so on.

cube of 2= 8, (ends with 8),cube of 12= 1728 (ends with 8), and so on.

cube of 3= 27, (ends with 7),cube of 13= 2147 (ends with 7), and so on.

cube of 4= 64,(ends with 8),cube of 148 (ends with 4), and so on...

cube of 5= 125,(ends with 8),cube of 15 (ends with 5), and so on...

cube of 6= 216,(ends with 8),cube of 16 (ends with 6), and so on...

cube of 7= 343,(ends with 8),cube of 17 (ends with 3), and so on...

cube of 8= 512,(ends with 8),cube of 18 (ends with 2), and so on...

cube of 9= 729,(ends with 8),cube of 19 (ends with 9), and so on...

cube of 10= 1000, cube of 20= 8000, cube of 30= 27000, cube of 40 = 64000, and so on.

To find the cube root of a cubic number (lets take the cubic number at most of 6- digits)

1 Take triplets from right.

2 decide the unit place of the cuberoot by looking at the unit place of the cube number.

Unit's place in the cubic number Unit's place in the cubic number

1 1

2 8

3 7

4 4

5 5

6 6

7 3

8 2

9 9

ends with 3 zeros ends with one zero

and so on.

3 decide the 10's place of the cuberoot by looking at the the cube number.

the cubic number(x) Unit's place in the cubic number

0≤x

1000≤x

8000≤x

27000≤x

64000≤x

125000≤x

216000≤x

343000≤x

512000≤x

729000≤x

and so on.

Example-

Find cuberoot of 314432.

314432 ends with 2, so unit place of cuberoot of 314432 is 8.

216000≤314432

**So cuberoot of 314432 i= 68.**