Justin is exchanging dollars for quarters and rolls of dimes each roll of quarters has value of 10$ and each roll of dimes has value of 5$ he exchanges 90$ and gets 11 rolls of coins how many of each type of coins did he get

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?