Question

Without doing any calculation, find the numbers which are surely not perfect squares:
$153$
$257$
$408$
$441$

• A. $153,257and441$ are surely not perfect squares.
• B. $441,257and408$ are surely not perfect squares.
• C. $153,441and408$ are surely not perfect squares.
• D. $153,257and408$ are surely not perfect squares.

Answer 1

The correct option is D $153,257and408$ are surely not perfect squares.

We know that a number ending in $2,3,7or8$ is answer for not being a perfect square. Therefore,
$153$ is not a perfect square.
$257$ is not a perfect square.
$408$ is not a perfect square.
$441$ may be a perfect square.
So, $153,257and408$ are surely not perfect squares.