Question

$1057$ is not a perfect square. Give reason.

• A. Because last two digits are $57$
  
• B. Because last digit of a number is ending with $7$
  
• C. Because sum of all the digits is $13$
• D. Data insufficient
  

Answer 1

Answer: (B)

Because last digit of a number is ending with $7$

All the perfect square end with any one from $0,1,4,5,6,9$

Since $1057$ ends with $7$

Hence, it is not a perfect square.

Option (B) is correct.