What is the domain of the function expressed by this formula?<br><br> Y= 1/x

Complete the sentence to show the distributive property of 7x6=

Ludmilka [50]

7×6=42 or 6×7=42 just change the numbers around but you get the same answer

3 0

3 years ago

A box contains 5 red and 5 blue marbles. Two marbles are withdrawn randomly. If they are the same color, then you win $1.10; if

topjm [15]

Answer:

a) The expected value is $\frac{-1}{15}$

b) The variance is $\frac{49}{45}$

Step-by-step explanation:

We can assume that both marbles are withdrawn at the same time. We will define the probability as follows

#events of interest/total number of events.

We have 10 marbles in total. The number of different ways in which we can withdrawn 2 marbles out of 10 is $\binom{10}{2}$ .

Consider the case in which we choose two of the same color. That is, out of 5, we pick 2. The different ways of choosing 2 out of 5 is $\binom{5}{2}$ . Since we have 2 colors, we can either choose 2 of them blue or 2 of the red, so the total number of ways of choosing is just the double.

Consider the case in which we choose one of each color. Then, out of 5 we pick 1. So, the total number of ways in which we pick 1 of each color is $\binom{5}{1}\cdot \binom{5}{1}$ . So, we define the following probabilities.

Probability of winning: $\frac{2\binom{5}{2}}{\binom{10}{2}}= \frac{4}{9}$

Probability of losing $\frac{(\binom{5}{1})^2}{\binom{10}{2}}\frac{5}{9}$

Let X be the expected value of the amount you can win. Then,

E(X) = 1.10*probability of winning - 1 probability of losing = $1.10\cdot \frac{4}{9}-\frac{5}{9}=\frac{-1}{15}$

Consider the expected value of the square of the amount you can win, Then

E(X^2) = (1.10^2)*probability of winning + probability of losing = $1.10^2\cdot \frac{4}{9}+\frac{5}{9}=\frac{82}{75}$

We will use the following formula

$Var(X) = E(X^2)-E(X)^2$

Thus

Var(X) = $\frac{82}{75}-(\frac{-1}{15})^2 = \frac{49}{45}$

7 0

3 years ago

Using the sum or difference formulas,how do we find the exact value of sin (285°)?

Semenov [28]

See attachment for the answer:

6 0

3 years ago

Can you explain how to solve for this

icang [17]

Answer:

we know the plane line has 180°

so here it's 111°-180° = 69°

so co- interior angles are equal so 111°=the olace of 13x-6

4 0

3 years ago

A pharmaceutical company is developing a new oral medication for the treatment of psoriasis, a skin disease marked by red, itchy

xeze [42]

Let's say we had a sample of 100 people. We'll split them into two equal groups of 50 each. The two groups will be the treatment and control groups. The treatment group, aka experimental group, is where the actual drug is given. The control group is where the fake drug is given. People in the control group must not know the pill is fake. For more info, check out the placebo effect. In short, this is when a person takes a fake pill and thinks they get better, and that positive mentality helps them actually get better.

If both the treatment and control groups improve (on average) together, then that means the fake pill is just as good as the real thing. Consequently, it means the real pill isn't effective at all. If on the other hand the experimental group does better overall compared to the control group, then we can see that the real pill is doing what it's intended to do. Of course, there are a lot of complicated factors involved, as there is with anything dealing with medicine. I haven't mentioned anything about side effects or things of that nature. In this simplified viewpoint of the world, we're only considering the one factor of whether or not the drug clears up the psoriasis on the skin.

To make things fair, it's best to randomly generate numbers so that you randomly assign people into each group. That way you have representative samples. Also, when drawing the sample of 100 people, make sure that's as random as possible to help represent the population as best as possible. The fact that the people in the control group not knowing that they are taking the fake pill means we have a single blind experiment. A double blind experiment is when even the researchers are not sure who is taking the real pill vs the fake pill. Double blind experiments are encouraged to prevent the researcher's bias from affecting the results.

To keep participants from knowing whether or not they are in the control group, the common solution is to provide a sugar pill. The pill will not cause any side effects and will not cause any improvements to health. It's simply sugar. To the participant, it seems like the real thing since they can't taste the difference or detect anything seems different.

6 0

3 years ago

Read 2 more answers

What is the domain of the function expressed by this formula? Y= 1/x - 7