Emily has a total of 20 dimes and nickels. if the dimes were nickels and nickels were dimes she would have 20 cents less than she has now.
write a system of equations that represents the problem(2 pts)

how many of each coin does she have(2 pts)?

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?