In a classroom the number of girls is 3 and 2/3 times the number of boys. there are 16 more girls than boys. find the total number of students in the classroom. explain your answer.

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?