Cube and Cube Root Shortcut Tricks

CUBE up to 30

13=1 113=1331 213=9261
23=8 123=1728 223=10648
33=27 133=2197 233=12167
43=64 143=2744 243=13824
53=125 153=3375 253=15625
63=216 163=4096 263=17576
73=343 173=4913 273=19683
83=512 183=5832 283=21952
93=729 193=6859 293=24389
103=1000 203=8000 303=27000

 

Find Five digit Cube and cube root Tricks

Find Five digit Cube and cube root Tricks

Need to remember 1 to 10 cube and this so easy for any one.Which will help in obtaining cube and cube root numbers.

13=1

23=8

33=27

43=64

53=125

63=216

73=343

83=512

93=729

103=1000

 

Find Five digit Cube and cube root Tricks

Need to remember 1 to 10 cube and this so easy for any one.

Example 1:

313824 = ?
Answer :
Step 1: Last digit of cube number from right side is 4 that we consider 64 = 43 we put down 4. Then
Step 2: Take the number whose cube is nearest to 13.
That is 13 is nearest to 23 and 33 we take small one cube digit that is 2.313824
So the answer is 24.

Example 2:

315625= ?
Answer :
Step 1: Last digit of cube number from right side is 5 that we consider 125 = 53 we put down 5. Then
Step 2: Take the number whose cube is nearest to 15.That is 15 is nearest to 23 and 33 we take small one cube digit that is 2.
So the answer is 25.

Example 3:

342875= ?
Answer :
Step 1: Last digit of cube number from right side is 5 that we consider 125 = 53 we put down 5. Then
Step 2: Take the number whose cube is nearest to 42.That is 42 is nearest to 33 and 43 we take small one cube digit that is 3.
So the answer is 35.

Find Six digit Cube and cube root Tricks

Find Six digit Cube and cube root Tricks

Need to remember 1 to 10 cube and this so easy for any one.Which will help in obtaining cube and cube root numbers.

13=1

23=8

33=27

43=64

53=125

63=216

73=343

83=512

93=729

103=1000

Find Seven digit Cube and cube root Tricks

Find Seven digit Cube and cube root Tricks

Need to remember 1 to 20 cube and this so easy for any one.Which will help in obtaining cube and cube root numbers.

13=1 113=1331
23=8 123=1728
33=27 133=2197
43=64 143=2744
53=125 153=3375
63=216 163=4096
73=343 173=4913
83=512 183=5832
93=729 193=6859
103=1000 203=8000

 

Find Seven digit Cube and cube root Tricks

Need to remember 1 to 20 cube and this so easy for any one.

Example 1:

3√3869893 = ?

Answer :
Step 1: Last digit of cube number from right side is 3 that we consider 343 = 73 we put down 7. Then
Step 2: Take the number whose cube is nearest to 3869.That is 3869 is nearest to 153 and 163 we take small one cube digit that is 15.

3√3869893
So the answer is 157.

Example 2:

3√1728000 = ?
Answer :
Step 1: Last digit of cube number from right side is 0 that we consider 1000 = 103 we put down 0. Then
Step 2: Take the number whose cube is nearest to 1728.That is 1728 is nearest to 123 and 133 we take small one cube digit that is 12.

3√3869893
So the answer is 120.

 

Shortcut to find cuberoot of any 5 or 6 digit number

Shortcut to find cube root is especially helpful in competitive exams where every second counts.
By using this method you can save a lot of time and also get accurate results.

Shortcut to mentally find the cube root of any 5 or 6 digit number

Step 1:Find the cube root of the last digit.
Points to be remembered while using this method.

(1)If the last digit is 8 then cube root will be 2.
(2)If the last digit is 2 then cube root will be 8.
(3)If the last digit is 7 then cube root will be 3.
(4)If the last digit is 3 then cube root will be 7.
(5)If the last digit is any other digit other than 2,8,3,7 then put the same number.
From this step you will get the unit’s or one’s place digit.

To find the tenth place digit you need to follow the below steps.
Step 2:Strike out the last 3 digits of the given number.

Step 3: find the nearest cube of the remaining number.

Step 4: find the cube root of the nearest cube which will give you ten’s place digit.

List of cubes to be memorized

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

NOTE: Shortcut to find cuberoot of any 5 or 6 digit number is applicable only if the given number is a perfect cube.
You can verify whether the given number is a perfect cube or not by using the Prime Factorization Method. If you are not familiar with this method check it here.

Let me explain this with an example to make things more clear and easy to understand.
So lets say we want to find the cube root of a 6 digit number 15746

Example 1:Find the cube root of 157464 in 5 seconds.

∛157464=?
Step 1:First we need to find the cube root of the last digit of the given number.
Here the last digit is 4 . 4 is a number other than 2, 8, 3, 7
hence we put the number as it is.
We get our one’s place digit as 4.

Now to get tenth place digit
Step 2: We need to strike the last 3 digits of the given number.
In this example the last 3 digits are 464 which we will strike off as shown below
157464

           Step 3:We need to find the nearest cube to the remaining number(157)
                      We find that 125 is the nearest cube to 157.
           Step 4: We need to find the cube root of the nearest cube(125)
                     ∛125=5
                      From this step we get our ten’s place digit as 5.
          From step 1 and step 4 we get the
          ∛157464=54

 

Ans:54

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