All categories

3 years ago

Need a quick answer please

Mathematics

1 answer:

mars1129 [50]3 years ago

8 0

Answer:

Step-by-step explanation:

Y = 1 because if you have 1/x that whould meant it would be 1 so y equals 1

You might be interested in

What Is the Formula For The Pythagorean Theorem? Thank You and Have a Nice Day.

vodomira [7]

This is the formula c=a2+b2

4 0

3 years ago

A manager forecasts that 150 guests will be served tomorrow. The manager knows that one server can provide high quality service

iVinArrow [24]

Answer:

5 servers and 3 cooks(since a person doesn't exist in fraction)

Step-by-step explanation:

From the question provided above, the manager(who is obviously organizing some kind of party or get-togethers) is expecting a hindered and fifty guests in total .

And it also says that if a server can handle 30 guests and 150,how many of them are need?

Let X be number of servers needed:

X= 150/30 = 5 servers

AND

If a single cook can prepare meals for 60 guests,the number of cooks required to cover for 150 guest will be:

X= 150/60 = 2.5,but since a fraction of a human doesn't exist, we have to say that the manager needs 3 cooks(2 of them will handle a total of 120 guests and the other cook handles the 30 guests)

6 0

3 years ago

On the left bottom, im not sure what to do there

egoroff_w [7]

I believe that it wants you to classify the kind of triangle each triangle is, but I’m not sure.

7 0

3 years ago

Identify which of these types of sampling is used: random, systematic, convenience, stratified, or cluster. To determine her

Artist 52 [7]

Answer:

achievements

Step-by-step explanation:

6 0

3 years ago

jon flips a fair coin until a head is witnessed, and independently anna flips a fair coin (a different coin than jon’s) until a

Readme [11.4K]

a) The pmf for w for certain value n is P(W = n) = 3 / 2²ⁿ⁺², b) The expected value on w, E(w) = 4 / 3, c) The expression for P(w ≥ k) = $\frac{1}{2}^{2k}$ , where k = 1, 2, 3...

Given: Jon flips a fair coin until a head is witnessed.

Anna flips a fair coin independently until a head is witnessed.

What is the probability density function?
The probability density function is a function that determines the probability for a discrete random variable X over a given sample space S for a certain value for X = x(some value).

It is also denoted as pmf and is written as P(X = x).

Let's solve the given question:

Let us assume the number of flips Jon did until he got a head to be X.

Also as Anna's flip independently so we need to consider a different random variable say Y.

So, the probability mass function for Jon (X) for a certain value of x is:

P(X = x) = $\frac{1}{2} * (1 - \frac{1}{2})^{x-1}$ , where x = 1, 2, 3, ...........

P(X = x) = $\frac{1}{2}*\frac{1}{2}^{x - 1}$

P(X = x) = $\frac{1}{2}^{x - 1 + 1}$

P(X = x) = $\frac{1}{2}^x$ , where x = 1, 2, 3, ........

Similarly, for Anna, we will have the same probability mass function but with a different random variable Y for a certain value of y

P(Y = y) = $\frac{1}{2}^y$ , where y = 1, 2, 3, ........

Now it is given that, w is the minimum number of flips between Jon and Anna.

w = minimum(P(X = x), P(Y = y))

Let us suppose the probability mass distribution over w is n for a certain value.

Then

P(w ≥ n) = P(minimum(P(X = x), P(Y = y)) ≥ n)

= $\frac{1}{2}^n * \frac{1}{2}^n$

= $\frac{1}{2}^{2n}$

Therefore, the probability mass function for w is

P(W = n) = P(W ≥ n) - P(W ≥ n + 1)

= $\frac{1}{2}^{2n}\\$ - $\frac{1}{2}^{2(n+1)}$

= $\frac{1}{2}^{2n}$ - $\frac{1}{2}^{2n + 2}$

= $\frac{1}{2}^{2n}$ ( 1 - $\frac{1}{2}^{2}$ )

= $\frac{1}{2}^{2n}$ ( 1 - 1 / 4)

= $\frac{1}{2}^{2n}$ (4 - 1) / 4

= 3 / 4 ( $\frac{1}{2}^{2n}$ )

= 3 / 2² ( $\frac{1}{2}^{2n}$ )

= 3 / 2²ⁿ⁺²

Now the expected value of w, E(w) is:

E(w) = ∑P(w ≥ i) where i = 0 to ∞

= ∑ $\frac{1}{2^{2i}}$ <em> </em>where i = 0 to ∞

= 1 + 1 / 4 + 1 / 16 + .......

This is infinite GP series. So the summation of infinite GP is

S = a / ( 1 - r )

where a is the first term, r is the power and s is the summation.

Here a = 1, r = 1 / 4

S = 1 / (1 - 1 / 4)

S = 1 / 3 / 4

S = 4 / 3

Therefore, E(w) = 4 / 3

The expression for P(w ≥ k) is:

P(w ≥ k) = $\frac{1}{2}^{2k}$ , where k = 1, 2, 3...

Hence

a) The pmf for w for certain value n is P(W = n) = 3 / 2²ⁿ⁺²

b) The expected value on w, E(w) = 4 / 3

c) The expression for P(w ≥ k) = $\frac{1}{2}^{2k}$ , where k = 1, 2, 3...

Know more about "probability density function" here: brainly.com/question/14410995

#SPJ4

5 0

2 years ago