A box in a certain supply room contains four 40-W lightbulbs, five 60-W bulbs, and six 75-W bulbs. Suppose that three bulbs are randomly selected. a. What is the probability that exactly two of the

Respuesta :

Answer: The required probability is 0.30.

Step-by-step explanation:

Since we have given that

Number of 40-W lightbulbs = 4

Number of 60-W light bulbs = 5

Number of 75-W light bulbs = 6

Total bulbs = 4+5+6 = 15

We need to find the probability that exactly two of the 75-W light bulbs.

so, it becomes,

[tex]\dfrac{^6C_2\times ^9C_1}{^{15}C_3}\\\\=\dfrac{135}{455}\\\\=0.30[/tex]

Hence, the required probability is 0.30.