First step in finding the cube root of any number between 1
and 100, you will have to learn cube of numbers from 1 to 12.
1^{3}= 01 7^{3}=
343
2^{3}= 08 8^{3}=
512
3^{3}= 27 9^{3}=
729
4^{3}= 64 10^{3}=
1000
5^{3}= 125 11^{3}=
1331
6^{3}= 216 12^{3}=
1728
Note: The unit
place on cubing 1, 4, 5, 6, 9 and 0 is same but the unit place on cubing 2, 3,
7, 8 are not same.
Cube of 2’s unit place is 8; and cube of 8’s unit place is
2.
Similarly, the cube of 3’s unit place is 7; and cube of 7’s
unit place is 3.
One can easily find the cube root of any number between 13
and 100.

Find cube
root of 2197.
Step 1: Take last 3 digits aside i.e. 197.
Step 2: Now, you can see the last digit of number 197 is
‘7’ which a unit place digit of 3^{3}. It means the number (cube root of 2197) contains ‘3’ in its
unit place.
Step 3: Next, you have to find the tens place digit.
For this, take the remaining value i.e. ‘2’ of number 2197.
Step 4: You can see that ‘2’ (of number 2197) is
larger than 1 (cube of 1).
Step 5: Finally, you know the cube root of 2197 by
combining the steps 2 and 4, which gives you the answer i.e. 13

Find the cube
root of 262144.
Step 1: Take last 3 digits
aside i.e. 144.
Step 2: Now, you can see the
last digit of number 144 is ‘4’ which a unit place digit of 4^{3}. It
means the number (cube root of 262144)
contains ‘4’ in its unit place.
Step 3: Next, you have to
find the tens place digit. For this, take the remaining value i.e. ‘262’ of
number 262144.
Step 4: You can see that
‘262’ (of number 262144) is larger than 216 (cube of 6).
Step 5: Finally, you know
the cube root of 262144 by combining the steps 2 and 4, which gives you the answer
i.e. 64
Practice:
1. Find the cube root of
474552.
2. Find the cube root of
140608.
3. Find the cube root of
704969.
4. Find the cube root of
421875.
5. Find the cube root of
79507.
6. Find the cube root of
175616.
 I have also share this post with my friend on
sscnaukri.in (
blog ssc aspirants).
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