Question

What is the square root of $156.25$ using long division method.

• A. $12.3$
• B. $12.5$
• C. $12.4$
• D. $12.7$

Answer 1

The correct option is B $12.5$

The following steps to find the square root by long division method
1. Draw lines over pairs of digits from right to left.
2. Find the greatest number whose square is less than or equal to the digits in the first group.
3. Take this number as the divisor and quotient of the first group and find the remainder.
4. Move the digits from the second group besides the remainder to get the new dividend.
5. Double the first divisor and bring it down as the new divisor.
6. Complete the divisor and continue the division.
7. Put the decimal point in the square root as soon as the integral part is exhausted.
8. Repeat the process till the remainder becomes zero.

Divisor $\downarrow$	Quotient $\downarrow$ 12.5
1	$\overline{1}$ $\overline{56}$.$\overline{25}$ 1 _______
22	56 44 _______
24.5	12.25 12.25 ______ 0 $\leftarrow$ Remainder

$\sqrt{156.25}=12.5$