Question

Predict the square root of $2916$ using Vilokanam method.

• A. $54$
• B. $44$
• C. $56$
• D. $46$

Answer 1

The correct option is A $54$

Square root of $2916$ using vilokanam method

$\Rightarrow$ It's unit Digit is $6$, therefore the unit digit of a square root will be $4$ or $6$.

$\Rightarrow$ Ignoring last two Digits(unit & ten's digit) we get $29$.

$\Rightarrow$ The greatest number whose square is less than are equal to $29$ is $5$

$\Rightarrow$ Adjusting above obtained two unit digits $4$ or $6$ to the right of $5$, we get two numbers. $54$ & $56$

$\Rightarrow$ The unique number with unit digit $5$ which lies between $54$ & $56$ is $55$

$(55{)}^2=(5\times 6)\cdot 25=3025$

by Ekadhikeva sutra

Since $2916<3025$

the square root required is $54$.