Estimating Cube Root
Estimating Cube Root, this method will work only if the given number is a perfect cube. The following are the steps to estimate the cube root.Step I : Make groups of 3 digits from unit(one's) place.This the 1st group.The remaining number makes the 2nd group.
Step II : The unit's digit of the 1st group will decide the unit digit of the cube root.( if the unit digit of the cube is 6 then the unit digit of cube root will also 6 as 6 x 6 x 6 = 3 6 ).
Step III : Find the cube of numbers between which the 2nd group lie.
Step IV : Take the smaller number as its ten's digit.
Unit digit of a given number  Unit digit of cube root 














Examples on estimating cube root :
1) Find the cube root of 238328.
Solution :
238328 is an even number so its cube root has to an even number.
Make two groups > 238328
First group 328 > unit digit is 8 so unit digit of cube root will be 2.
(see the above table).
Second Group 238 > it lies between 6 ^{3} =216 and 7 ^{3} =343 .
So take the smaller number 6 as ten's place.
∴ ∛238328 = 62
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2) Find the cube root of 175616.
Solution :
We know that ∛175616 =  ∛175616
The number is even so its cube root has to an even number.
Make two groups > 175616
First group 616 > unit digit is 6 so unit digit of cube root will be 6
(see the above table).
Second Group 175 > it lies between 5 ^{3} =125 and 6 ^{3} = 216 .
So take the smaller number 5 as ten's place.
Cube and Cube Roots
• Cube of Numbers
• Perfect Cube
• Properties of Cube
• Cube by Column method
• Cube of Negative numbers
• Cube of Rational numbers
• Cube Root
• Finding cube root by Prime Factorization
• Cube root of Rational numbers
• Estimating cube root
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