A bag contains 2 red pens, 4 blue pens, 3 black pens, and 1 green pen. Once a pen is selected, it is replaced, and then another pen is selected. Determine P(blue and blue)

Respuesta :

Given:

A bag contains 2 red pens, 4 blue pens, 3 black pens, and 1 green pen.

Once a pen is selected, it is replaced, and then another pen is selected.

To find:

The probability of getting blue pens in both draws, i.e., P(blue and blue).

Solution:

We have,

Number of red pens = 2

Number of blue pens = 4

Number of black pens = 3

Number of green pen = 1

Total number of pens = [tex]2+4+3+1[/tex]

                                    = [tex]10[/tex]

The probability of getting a blue pen is:

[tex]P(\text{Blue})=\dfrac{\text{Number of blue pens}}{\text{Total number of pens}}[/tex]

[tex]P(\text{Blue})=\dfrac{4}{10}[/tex]

[tex]P(\text{Blue})=0.4[/tex]

Once a pen is selected, it is replaced, and then another pen is selected. So, after replacement the probability of getting a blue is remains the same.

[tex]P(\text{Blue and Blue})=P(\text{Blue})\times P(\text{Blue})[/tex]

[tex]P(\text{Blue and Blue})=0.4\times 0.4[/tex]

[tex]P(\text{Blue and Blue})=0.16[/tex]

Therefore, the value of [tex]P(\text{Blue and Blue})[/tex] is 0.16.