A school bus can hold a maximum of 45 students. The correct inequality for this word problem is b ≤ 45. Why did I use ≤ not < in this problem?

The number if marbles of different colors stored in a hat is listed below: 4 red marbles 10 green marbles 7 blue marbles. without looking in the hat, dan takes out a marble at random. he replaces the marble and then takes out another marble from the hat. what is the probability that dan takes out a blue marble in both draws?