There are a total of 51 students in the Modern Dance and Ballet classes. The Modern Dance class has twice as many students as the Ballet class. Write a system of linear equations that represent this situation. How many students are in each class?

Abag contains 3 red marbles, 2 blue marbles, and 2 green marbles. one marble is picked, then another marble. assume that the selections are made with replacement. a) find the probability of picking two red marbles with replacement. b) find the probability of picking a red marble and a blue marble. assume the selections are made without replacement. c) find the probability of picking two red marbles without replacement. d) find the probability of picking a red marble and a blue marble without replacement.