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
1 Cube of 1 ends with 1
23
8 Cube of 2 ends with 8
33
27 Cube of 3 ends with 7
43
64 Cube of 4 ends with 4
53
125 Cube of 5 ends with 5
63
216 Cube of 6 ends with 6
73
343 Cube of 7 ends with 3
83
512 Cube of 8 ends with 2
93
729 Cube of 9 ends with 9
103
1000 Cube 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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15 comments:

  1. Raj Kumar KashyapJune 19, 2015 at 6:00 PM

    q-7 ka ans wrong hai

    ReplyDelete
  2. Last wale digit ka bhi cube kar do list dekhne ki jarurat hi nhi padegi

    ReplyDelete
  3. Please post English material if anybody have

    ReplyDelete
  4. thank u sir ji ...

    ReplyDelete
  5. there are 2 possible combinations here...

    E,I,H,L,G,F,J,K(Starting from top most ie 8th floor)

    and E,I,H,K,G,F,J,L(Starting from top most ie 8th floor)

    ReplyDelete
  6. Ye to 6 digit pe based Thai agar isme 8 digit ho to kese solve hoga

    ReplyDelete
  7. no there is only one possible combination....the second one...
    coz L does not possess yellow color car...as given in the ques...

    ReplyDelete
  8. ya...correct :)Thanx Sonam...n all d best :)

    ReplyDelete
  9. plz solve this ques
    Eight friends P,Q,R,S,T,U,V,W and Y are sitting around a square table in such a way that four of them sit at the four corners of the square while four sit in the middle of each of the four sides. The ones who sit at the four corners face the centre while those who sit in the middle of the sides face outsides.
    P who faces the centre sits third to the right of V.
    T,who faces the centre is not an immediate neighbour of V and W
    S sits second to right of Q.
    Q faces the centre.
    R is not an immediate neighbour of P

    ReplyDelete
  10. easy one solve ho gai................order in clockwise direction will be as-- TRSVQWPU

    ReplyDelete

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