Estimating Cube Root
Covid-19 has led the world to go through a phenomenal transition .
E-learning is the future today.
Stay Home , Stay Safe and keep learning!!!
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
_______________________________________________________________
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
Home Page
Covid-19 has affected physical interactions between people.
Don't let it affect your learning.