A box contains 4 red markers and 2 blue markers a marker is selected at random and it's color is noted. If it is red it is replaced; otherwise it is not. A second marker is selected and it's color is noted. If the second is blue, find the probability that the first was blue?

Step-by-step explanation:

In the given box, there are 4 red markers and 2 blue markers.

The given scenario will not affect the required probability as the selection of the second one is a case of future.

We need to find the probability of the first marker is blue.

The probability is .

h is the x-coordinate of the vertex

step-by-step explanation:

we have

in this function

the point represent the vertex of the function

so

h is the x-coordinate of the vertex

k is the y-coordinate of the vertex