Question

What is a perfect square number among 156, 289, 300, and 420?

Answer 1

Finding the perfect square number among $156,289,300,$and $420.$

A number made by squaring a whole number is called perfect square number.

Now ,

Prime factors of $156=2\times 2\times 3\times 13$.

As $156$ cannot be expressed as square of a whole number. So $156$ is not a perfect square.

Prime factors of $289=17\times 7$.

As $289$ can be expressed as square of a whole number $17$. So $289$ is a perfect square.

Prime factors of $300=2\times 2\times 3\times 5\times 5$

.As $300$ cannot be expressed as square of a whole number. So $300$ is not a perfect square.

Prime factors of $420=2\times 2\times 3\times 5\times 7$

.As $420$ cannot be expressed as square of a whole number. So $420$ is not a perfect square.

Therefore, $289$ is a perfect square among $156,289,300,$and $420$.