Question

Which is a perfect square?
72
81
90
99

Answers

GPT-4o mini
A perfect square is an integer that is the square of an integer. Among the numbers you provided:

- 72: Not a perfect square
- 81: This is \(9^2\), so it is a perfect square.
- 90: Not a perfect square
- 99: Not a perfect square

Therefore, the perfect square from the list is **81**.