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2 years ago

11

Plz help me with this

1 answer:

hammer [34]2 years ago

7 0

Answer: mean = 3.6, standard deviation = 3

<u>Step-by-step explanation:</u>

$\text{Mean: }\dfrac{90\times 4}{100}=\dfrac{360}{100}=3.6\\\\\\\text{Standard Deviation: }\\\bullet n=100\qquad \rightarrow \text{number of students}\\\bullet p=0.9\qquad \rightarrow \text{probability of success}\\\bullet q=0.1\qquad \rightarrow \text{probability of failure}\\\\SD=\sqrt{n\times p\times q}\\.\quad =\sqrt{(100)(0.9)(0.1)}\\.\quad =\sqrt{9}\\.\quad =3$

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Kayla has 1,000 Apples in 5 bags, Mack has 999 apples in 5 bags as well, how many apples does Kayla have THAN Mack? Mack said th

sesenic [268]

Kayla is correct because if she has 1,000 and Mack has 999, then that means he needs only one more Apple to be equal with Kaylas amount of apples . 999+ 1 = 1,000

6 0

3 years ago

NO LINKS OR ANSWERING QUESTIONS YOU DON'T KNOW!!! THIS IS NOT A TEST OR AN ASSESSMENT!! Please help me with these math questions

Art [367]

Answer:

See below

Step-by-step explanation:

3. What are two ways that a vector can be represented?

Considering a vector $\vec{v}$ in some vector space $\mathbb R^n$ we have

$\vec{v} = \langle a,b\rangle$

This is the component form. I don't like that way. It is probably used in high school, but

$\vec{v} = \begin{pmatrix} a\\ b\\ \end{pmatrix}$

is preferable because the inner product on $\mathbb R^n$ is defined to be

$\langle a,b\rangle := \sum_{i = 1}^n a_i b_i$

You can also write it using linear form such as $\vec{v} = 2i+2j$

4.

For this question, I think you meant

vectors

$\vec{u_1} = (-8, 12)$

$\vec{u_2} = (13, 15)$

Once

$\cos(\theta)=\dfrac{\vec{u_1} \cdot\vec{u_2}}{||\vec{u_1}||||\vec{u_2}||}$

Considering that the dot product is

$\vec{u_1}\cdot \vec{u_2} = (-8)\cdot 13 + 12\cdot 15 = -104+180= 76$

and the norm of $\vec{u_1}$ is $||\vec{u_1}|| = \sqrt{(-8)^2 + 12^2} = \sqrt{64 + 144}= \sqrt{208}$

and the norm of $\vec{u_2}$ is $||\vec{u_2}|| = \sqrt{13^2 + 15^2} = \sqrt{169 + 225}= \sqrt{394}$

Thus,

$\cos(\theta)=\dfrac{76}{\sqrt{208} \sqrt{394}} = \dfrac{19}{\sqrt{13}\sqrt{394}}=\dfrac{19}{\sqrt{5122}}$

$\therefore \theta = \arccos \left(\dfrac{19}{\sqrt{5122}} \right)$

3 0

2 years ago

Using partial products the products are 21 and 28 true or false

Allisa [31]

21 times 28 is 588 which is false

4 0

3 years ago

The mean of four consecutive even numbers is 15.

mote1985 [20]

Find what the sum of the #s could be by multiplying 15*4 since there's 4 #s . 15*4=60 so the sum of the 4 #s is 60

4 0

3 years ago

What are the solutions to the equation |x| =15 -4x?

zheka24 [161]

I hope this helps you

5 0

3 years ago