Atotal of $30 was placed in 4 envelopes, each one with a different amount. money from the largest share was taken to double each of the other amounts. the resulting amounts were the same as before, but in different envelopes. what were the four amounts of money?

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?