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2 years ago

Heyy can someone help?

Mathematics

2 answers:

lozanna [386]2 years ago

7 0

I think the answer is the third one. I hope it’s the right answer if not then I’m really sorry. Hope you have a nice day:)

IrinaK [193]2 years ago

6 0

Answer:

It is #3

Step-by-step explanation:

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. Ryleigh received a $50 gift card to the frozen yogurt shop for her birthday. The shop sells yogurt sundaes for four dollars an

Ede4ka [16]

Where is the graph I can help but I will need to see the graph

6 0

3 years ago

What is the formula for the expected number of successes in a binomial experiment with n trials and probability of success p? C

charle [14.2K]

Answer:

$(D)E[ X ] =np.$

Step-by-step explanation:

Given a binomial experiment with n trials and probability of success p,

$f(x)=\left(\begin{array}{c}n\\k\end{array}\right)p^x(1-p)^{n-x}, 0\leq x\leq n$

$E(X)=\sum_{x=0}^{n}xf(x)= \sum_{x=0}^{n}x\left(\begin{array}{c}n\\k\end{array}\right)p^x(1-p)^{n-x}$

Since each term of the summation is multiplied by x, the value of the term corresponding to x = 0 will be 0. Therefore the expected value becomes:

$E(X)=\sum_{x=1}^{n}x\left(\begin{array}{c}n\\x\end{array}\right)p^x(1-p)^{n-x}$

Now,

$x\left(\begin{array}{c}n\\x\end{array}\right)= \frac{xn!}{x!(n-x)!}=\frac{n!}{(x-)!(n-x)!}=\frac{n(n-1)!}{(x-1)!((n-1)-(x-1))!}=n\left(\begin{array}{c}n-1\\x-1\end{array}\right)$

Substituting,

$E(X)=\sum_{x=1}^{n}n\left(\begin{array}{c}n-1\\x-1\end{array}\right)p^x(1-p)^{n-x}$

Factoring out the n and one p from the above expression:

$E(X)=np\sum_{x=1}^{n}n\left(\begin{array}{c}n-1\\x-1\end{array}\right)p^{x-1}(1-p)^{(n-1)-(x-1)}$

Representing k=x-1 in the above gives us:

$E(X)=np\sum_{k=0}^{n}n\left(\begin{array}{c}n-1\\k\end{array}\right)p^{k}(1-p)^{(n-1)-k}$

This can then be written by the Binomial Formula as:

$E[ X ] = (np) (p +(1 - p))^{n -1 }= np.$

5 0

3 years ago

Molly and henry went shopping for books molly bought 7 books for $42 and henry bought 8 book for $52 who got the better buy

Vesna [10]

Answer:

Molly

Step-by-step explanation:

because molly had

42 divided by 7

that gave her 6$ per book.

But Henry has

52 divided by 8

which is about 6.5.

That's why molly got the better deal.

3 0

3 years ago

Quan bought 8.6 meters of frabic. how many cm of fabric did he buy

stira [4]

When you convert from meters to centimeters, you always multiply by 100, which means that 1 meter = 1 * 100 cm = 100 cm
So, 8.6 meters = 8.6 * 100 cm = 860 cm

Hope this Helps :)

4 0

3 years ago

Read 2 more answers

Can someone please help me with this? I’m really confused on it.

trasher [3.6K]

For this problem you need to put the x values in for x in the equation. For example, put -10 in for x and calculate y, which is g(x)

8 0

3 years ago