Your friend brings 15 chocolate cupcakes and 15 vanilla cupcakes to school. students will take turns picking a pair of cupcakes at random. what is the probability that the first student will pick 2 chocolate cupcakes?

Probability says that divide the required possible outcomes by the total number of  outcome.

As per the statement:

Your friend brings 15 chocolate cupcakes and 15 vanilla cupcakes to school.

We have to find the probability that the first student will pick 2 chocolate cupcakes.

Number of required possible outcomes =

Total number of outcomes =

by definition we have;

We know that:

⇒

Using the formula:

⇒

⇒

Simplify:

therefore, the probability that the first student will pick 2 chocolate cupcakes is,  

to plot points   for x just start at the origin (middle) and go to the left however many times it say(if the number is a positive) if the number is a negative then go right however many times it says if it is 0 go nowhere

now keep you pencil there and go up however many times it says on y(if it is positive) if it is negative then go down however many times it says. if it says 0 go nowhere.

you have just plotted a point! now when you finish plotting all of them connect them with a ruler

plot each point as (-3, 7), (0,4), (3,1), (8,-4)   in the parenthesis on the left of the comma is x and the right is y.