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Short Tricks to find Cube Root

 To find out the cube roots of a perfect cube, you need to know some of the basic cubes

13= 1, 23 = 8, 33= 27, 43= 64, 53 = 125
63= 216, 73 =343, 83= 512, 93 = 729, 103 = 1000

13
1Cube of 1 ends with 1
23
8Cube of 2 ends with 8
33
27Cube of 3 ends with 7
43
64Cube of 4 ends with 4
53
125Cube of 5 ends with 5
63
216Cube of 6 ends with 6
73
343Cube of 7 ends with 3
83
512Cube of 8 ends with 2
93
729Cube of 9 ends with 9
103
1000Cube of 10 ends with 0

To find out the cube root of any perfect cube, follow the following steps:

Must read trick to find Square root

Find out the cube root of 19683.

Step 1: underline the last three digits and see it is ending with 3 that means
Explanation: Look at the table; we can see that cube of 7 ends with 3, so the unit digit of the required number would be 7 

Step 2: Now look in the table and find the greatest cube which is less than 19. We can see in this case it is 8 and its cube root is 2.

So the digit at tens place would be 2
Therefore the cube root of 19683 is 27.

Find out the cube root of 250047

Step 1: 250047

Last three digit ending with 7 , From the table a cube of 3 is ending with 7 is ,it means the unit digit would be 3 .

Step 2: Now see the first three digits .From the table we can see that the largest cube which is less than 250 is 216( 63). So the digit at tens place would be 6
Therefore the cube root of 250047 is 63.

Find the cube root of 175616.

Solution:

Step 1:
( ending with 6 and from the table we know that cube of 6 ends with 6.)

Step 2:


(largest cube which is less than 175 is 125 and it is the cube of 5 so the tens digit would be 5.)

There the cube root of 175616 is 56.

Find the cube root of 941192

Solution:

Step 1:
                                      (Ending with 2 and if we observe the table carefully, we see that cube of 8 ends with 2, so the digit at unit place would be 8)

Step 2 : 

                      (Largest cube less than 941 is 93=729 and therefore the digit at tens place would be 9.)

So the cube root of 941192 is 98.

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