I need some help with this please. You are buying a new backpack. You can choose it in the following colors: black, green, red, and gray. You can choose to have an outside pocket or no outside pocket.
a. Make a tree diagram to show how many different backpacks there are to choose from.
b. If you choose a backpack at random, what is the probability that it has an outside pocket?
c. What are the odds against you choosing a green backpack?