math
posted by Melissa on .
An urn contains 5 red marbles, 4 blue marbles, and 3 green marbles. A marble is selected at random and then, without replacing the first marble, a second marble is selected at random. What is the probability of selecting a green marble and then a red marble?

Green = 3/12
Red = 5/11, because one green marble has already been picked.
The probability of both/all events occurring if found by multiplying the probabilities of the individual events. 
15/132

Solve this problem.
A bag contains 5 red marbles, 7 green marbles, and 3 orange marbles. Find the probability of drawing a red marble. 
Li rolls a number cube that has sides labeled 1 to 6 and then flips a coin . What is the probability that she rolls an odd number and flips tail is it 1/8 or 1/4 or 1/2 or 3/4