Question

Find the square root of 784 by prime factorisation method.

• A. $22$
• B. $28$
• C. $18$
• D. $38$

Answer 1

The correct option is B $28$

$784=\underset{–}{2\times 2}\times \underset{–}{2\times 2}\times \underset{–}{7\times 7}\Rightarrow \sqrt{784}=2\times 2\times 7=28$