Cube Of Two Digit Number Less Than The Base


Cube With Yavadunam Method I - Concepts
Class - 7th Foundation NTSE Subjects
 
 
Concept Explanation
 

Cube Of Two Digit Number Less Than The Base

Cube of Two Digit Number Less Than The Base Using Yavadunam Method

This method is used to find the cube of a two digit number less than the base. It is a very efficient way of finding Cube. It saves a lot of time in competitive exam where each second counts and doing these type of calculations in normal ways consumes lot of our precious time.

Find Cube of 93

Step 1 : Find the deficit in the number as compared to the base. For 93 the nearest base is 100 so the deficit is 7 or we can say surplus will be -7   

We will double the surplus and add it to the number

Result 1 = -7 X 2 + 93 = -14 + 93 = 79   

Step 2: The surplus in the Result 1 that is 79 when the base is 100 is -21. We will multiply the surplus with the earlier surplus i.e. -7

Result 2= -21 X -7 = 147

Step 3: Find the Cube of the number that was surplus in step1. Cube of -7 is -343

Result 3 = -343 

Since the total zeros in the base are two, so two digits will we be prefixed in the answer at each step.

Step 4: As the Result 3 is negative We will borrow 1 from result 2 add 100 to the leftmost two digits of Result 3, Then the two digits will be prefixed in the answer and the remaining digits of Result 3 will be the carry.

Resultant Number= 100 -43 = 57 

Result 2 = 147-1 = 146 

Answer = 57    

Carry is -3                                         

Step 5: The carry is added to Result 2 Then the two digits will be prefixed in the answer and the remaining are the carry. If the digits are less than two then zeros are prefixed.

Resultant Number = 146-3 = 143  

Answer = 4357  

Carry is 1

Step 6: The Carry is added to the Result 1. The Resultant Number is Leftmost Block of the Answer

Resultant Number = 79 + 1 = 80      

Answer : 804357

 

 
Video Link - Have a look !!!
 
Language - English
 
 
 
 
Related Videos


Students / Parents Reviews [10]