Question

Which of the following numbers are not perfect squares?.

• A. 256
• B. 289
• C. 576
• D. 563

Answer 1

The correct option is D 563

$256=2\times 2\times 2\times 2\times 2\times 2\times 2\times 2$

$256=(2\times 2\times 2\times 2)\times (2\times 2\times 2\times 2)$

$256=16\times 16$

$\therefore$ $256={16}^2$

$289=17\times 17$

$289={17}^2$

$576=2\times 2\times 2\times 2\times 2\times 2\times 3\times 3$

$576=(2\times 2\times 2\times 3)\times (2\times 2\times 2\times 3)$

$576=24\times 24$

$\therefore$ ${24}^2$

$563=1\times 563$

$\therefore$ We can see, $256,289,576$ are perfect square and $563$ is not a perfect square.