Question

What is the smallest natural number which when added to the difference of squares of 17 and 13 gives a perfect square?

• A. 1
• B. 5
• C. 11
• D. 24

Answer 1

The correct option is A 1

${17}^2-{13}^2=289-169=120$
$120+1=121={11}^2$
Hence 1 is the added to make it a perfect square.