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. What is the probability that exactly three of the selected bulbs are rated 75-W? (15 points)

Probability that exactly three of the selected bulbs are rated 75-W is 0.044.

Step-by-step explanation:

We are given that a box in a certain supply room contains four 40-W light bulbs, five 60-W bulbs, and six 75-W bulbs.

And we have to find the probability that exactly three of the selected bulbs are rated 75-W.

Here, we will use Combinations for selection procedure, i.e.;

So, number of ways of selecting three 75-W rated bulbs from total of six 75-W rated bulbs in a box is given by =

Total number of ways of selecting three bulbs from total of 15 bulbs (4 + 5 + 6) in a box =

Therefore, probability that exactly three of the selected bulbs are rated 75-W is given as = =

                             = = =

                             = 0.044

Hence, the required probability is 0.044.

the one that has a slope of 1/2 and is positive.

step-by-step explanation: 2 buckets 1 trip ; 4 buckets 2 trips and so on.

the correct option is 2.

step-by-step explanation:

according to the given information triangle abc is a right angle triangle with right angle at a. segment ab is 5 and segment ac is 7. point d is on segment bc and angles adb and adc are right angles.

it is given that triangles abd, cad, and cba are similar.

two triangles are similar if their corresponding sides are proportional.

in triangle cba, using pythagoras theorem

                      )

triangle abd and cba are similar,

                            (2)

triangle cad and cba are similar,

                      )

using (1), (2) and (3), we get

hence proved.

therefore option 2 is correct.