can you please help me with this

Answer:

The percentage is  k  =  2.3%

Step-by-step explanation:

From the question we are told that

  The  population mean is  [tex]\mu = 47[/tex]

    The  standard deviation is  [tex]\sigma = 14[/tex]

Given that the sales are normally distributed and that students at a certain school who sell at least 75 magazine subscriptions win a prize then the  percent of the fourth grade students receive a prize is mathematically represented as

     [tex]P(X > 75) = P(\frac{X - \mu }{\sigma } > \frac{75 - \mu }{\sigma })[/tex]

Generally

     [tex]\frac{X - \mu }{\sigma } = Z (The \ standardized \ value \ of \ X )[/tex]

So

   [tex]P(X > 75) = P(Z > \frac{75 - 47 }{14 })[/tex]

   [tex]P(X > 75) = P(Z > 2)[/tex]

From the standardized normal distribution table  

      [tex]P(Z > 2) =0.023[/tex]

=>   [tex]P(X > 75) = 0.023[/tex]

The  percentage of the fourth grade students receive a prize is  

  k =  0.023 * 100

   k  =  2.3%

A certain​ animal's body temperature has a mean of 94.72° F and a standard deviation of 0.57°F. Convert the given temperatures to z scores.

a. 93.52 °F  b. 95.22 °F      c. 94.72 °F

Answer:

a. z = - 2.1053

b. z = 0.87719

c. z = 0

Step-by-step explanation:

Given that :

The population mean μ = 94.72

The standard deviation σ = 0.57

the formula for calculating the standard normal z score, which can be represented as:

[tex]z= \dfrac{\overline x - \mu}{\sigma}[/tex]

For  a.

The sample mean [tex]\bar x[/tex] = 93.52

The z score can be computed as follows:

[tex]z= \dfrac{\overline x - \mu}{\sigma}[/tex]

[tex]z= \dfrac{93.52 - 94.72}{0.57}[/tex]

[tex]z= \dfrac{-1.2}{0.57}[/tex]

z = - 2.1053

For  b.

The sample mean [tex]\bar x[/tex]  =  95.22    

[tex]z= \dfrac{\overline x - \mu}{\sigma}[/tex]

[tex]z= \dfrac{95.22 - 94.72}{0.57}[/tex]

[tex]z= \dfrac{0.5}{0.57}[/tex]

z = 0.87719

For  c.

The sample mean [tex]\bar x[/tex]  = 94.72

[tex]z= \dfrac{\overline x - \mu}{\sigma}[/tex]

[tex]z= \dfrac{94.72 - 94.72}{0.57}[/tex]

[tex]z= \dfrac{0}{0.57}[/tex]

z = 0

Answer:

= 2/3

Step-by-step explanation:

10 / (5*3)

= 10/15

= 2/3

Answer:

Y = 27

Step-by-step explanation:

Y * 3 = 81

Divide each side by 3

Y * 3/3 = 81/3

Y = 27

Answer:

c = 60.65 cm

Step-by-step explanation:

Given that,

The two sides of a triangle are 33 cm and 37 cm.

The angle between these two sides is 120°.

We need to find the length of the third side of the triangle. Let c is the third side. Using cosine rule,

[tex]c^2=a^2+b^2-2ab\cos C[/tex]

a = 33 cm, b = 37 cm and C is 120°

So,

[tex]c^2=(33)^2+(37)^2-2\times 33\times 37\cos (120)\\\\c=60.65\ cm[/tex]

So, the length of the third side of the triangle is 60.65 cm.

Answer:

27.5

Step-by-step explanation:

3 = 7.5

4 = 10

5*7.5=37.5-10=27.5

Seriously. 2=5 contradicts.

Answer:

[tex]P(Gray\ and\ Blue) = \frac{1}{4}[/tex]

Step-by-step explanation:

Given

[tex]Sections = 10[/tex]

[tex]n(Gray) = 5[/tex]

[tex]n(Blue) = 5[/tex]

Required

Determine P(Gray and Blue)

Using probability formula;

[tex]P(Gray\ and\ Blue) = P(Gray) * P(Blue)[/tex]

Calculating P(Gray)

[tex]P(Gray) = \frac{n(Gray)}{Sections}[/tex]

[tex]P(Gray) = \frac{5}{10}[/tex]

[tex]P(Gray) = \frac{1}{2}[/tex]

Calculating P(Gray)

[tex]P(Blue) = \frac{n(Blue)}{Sections}[/tex]

[tex]P(Blue) = \frac{5}{10}[/tex]

[tex]P(Blue) = \frac{1}{2}[/tex]

Substitute these values on the given formula

[tex]P(Gray\ and\ Blue) = P(Gray) * P(Blue)[/tex]

[tex]P(Gray\ and\ Blue) = \frac{1}{2} * \frac{1}{2}[/tex]

[tex]P(Gray\ and\ Blue) = \frac{1}{4}[/tex]

Answer:

The sum is represented by the polynomial:

[tex]5\,x^9+2 \,x^7+13\,x+4[/tex]

Step-by-step explanation:

Recall that polynomials are added by combining like terms. The only like terms in this addition are: 5 x and 8 x  which added render: 13 x. therefore, the addition of these polynomials renders;

[tex]5\,x^9+2 \,x^7+13\,x+4[/tex]

Answer:

4, 7, 10, 13

Step-by-step explanation:

Hey there!

Well in the given pattern,

-11, -8, -5, -2, 1

we can conclude that the pattern is +3 every time.

-11 + 3 = -8

-8 + 3 = -5

-5 + 3 = -2

-2 + 3 = 1

And so on

Hope this helps :)

Answer:$40.00

Step-by-step explanation:first divide 20 by 5 and the answer will be 4. now multiply 10 into 4 and you'll get the answer $40.00

Answer:

The equation is [tex]x(t) = -13 cos (8 \pi t )[/tex]

Step-by-step explanation:

From the question we are told that

      The  amplitude is  [tex]A = 13 \ in[/tex]

       The period is  [tex]T = 0.25[/tex]

Generally the displacement function for a simple harmonic motion is mathematically represented as

        [tex]x(t) = A cos (wt )[/tex]

Here  [tex]w[/tex] is the angular frequency which is mathematically represented as

          [tex]w = \frac{2 \pi }{T}[/tex]

substituting values

          [tex]w = \frac{2 \pi }{ 0.25}[/tex]

          [tex]w = 8\pi[/tex]

Given that at t =  0  the displacement is equal to 0 it means that there is no phase shift and also  we are told that it is initially moving downward which implies that its Amplitude is  [tex]A = -13\ in[/tex]

So the equation modeling the displacement d as a function of time t is mathematically represented as

          [tex]x(t) = -13 cos (8 \pi t )[/tex]

Answer:

ABC = 148, 3*148 = 444

Step-by-step explanation:

We know that 111 = 3*  37, so all numbers of the form BBB has the factor 37.

So we need a multiple of 37 such thant when multiplied, we get three digits the same as the middle digit.

Try 4*37 = 148, 148*3 = 444, bingo, we got the right combination.

So ABC is 148.

Answer:

[tex]\huge \boxed{x=3}[/tex]

Step-by-step explanation:

[tex]6(x+2)=30[/tex]

[tex]\sf Divide \ both \ sides \ by \ 6.[/tex]

[tex]x+2=5[/tex]

[tex]\sf Subtract \ 2 \ from \ both \ sides.[/tex]

[tex]x=3[/tex]

Answer:

3

Step-by-step explanation:

30 = 6(x+2)

30/6 = 5

5 = x+2

5-2 = 3

3=x

This is a pretty simple question and I tried to make it as simple as possible when explaining it.

Answer:

f(0) = 7

Step-by-step explanation:

f(x) = -3x + 7

Let x =0

f(0) = -3*0 + 7

f(0) = 7

Answer:

See the explanation and attached images for the answers.

Step-by-step explanation:

a) 1-step transition matrix:

See the attached image for transition matrix.

Let the matrix be M

if the stock closes higher on a day, the probability that it closes higher the next day is 0.65.

If the stock closes lower on a day, the probability that it closes higher the next day is 0.45

if the stock closes higher on a day, the probability that it closes lower the next day is 1 - 0.65 = 0.35

if the stock closes lower on a day, the probability that it closes lower the next day is 1 - 0.45 =0.55

b)

To compute probability for 3 days later multiply matrix M (from part a) thrice i.e. M*M *M

[tex]M^{3} = \left[\begin{array}{ccc}0.65&0.35\\0.45&0.55\end{array}\right]*\left[\begin{array}{ccc}0.65&0.35\\0.45&0.55\end{array}\right]*\left[\begin{array}{ccc}0.65&0.35\\0.45&0.55\end{array}\right][/tex]

[tex]M^{3} = \left[\begin{array}{ccc}0.65 * 0.65 + 0.35 * 0.45 &0.65 * 0.35 + 0.35 * 0.55 \\0.45 * 0.65 + 0.55 * 0.45 &0.45 * 0.35 + 0.55 * 0.55 \end{array}\right] * \left[\begin{array}{ccc}0.65&0.35\\0.45&0.55\end{array}\right][/tex]

[tex]M^{3} = \left[\begin{array}{ccc}0.58&0.42\\0.54&0.46\end{array}\right]*\left[\begin{array}{ccc}0.65&0.35\\0.45&0.55\end{array}\right][/tex]

[tex]M^{3} = \left[\begin{array}{ccc} 0.58 * 0.65 + 0.42 x 0.45&0.58 * 0.35 + 0.42 * 0.55 \\0.54 * 0.65 + 0.46 * 0.45 &0.54 * 0.35 + 0.46 * 0.55 \end{array}\right][/tex]

[tex]M^{3} = \left[\begin{array}{ccc}0.566&0.434\\0.558&0.442\end{array}\right][/tex]

The probability that it will close higher on Thursday is 0.566. See the transmission matrix of M³ for higher-higher. This can be interpreted as:

if the stock closed higher on Monday, the probability that it closes higher the on Thursday (three days later) is 0.566

Answer:

36ft³

Step-by-step explanation:

Bottom rectangular prism: 2x2x6=24

Top rectangular prism: 2x2x3=12

24+12=36ft³

Answer:

[tex]\boxed{36ft^3}[/tex]

Step-by-step explanation:

Hey there!

Well to solve for V we need to find the volume of the 2 rectangular prism's given.

Rec#1: 2•3•2 = 12

Rec#2: 6•2•2 = 24

Rec#1 + Rec#2 = V

12 + 24 = 36ft³

Hope this helps :)

Answer:

16/3 hours  5 1/3

Step-by-step explanation:

Answer: 5 1/3

Step-by-step explanation:

Answer:

5

Step-by-step explanation:

Just multiply 5/7 by 7 since his dog retrieved 5/7 out of the 7 ducks he shot.

Answer:

5

Step-by-step explanation:

7*5/7

7 represents the # of ducks

5/7 represents the # of ducks that were recovered

The question asks the number of ducks that were recovered so you should multiply the total # of ducks there are by the fraction that were recovered.

There are many examples to pick from, one is

point = location on map

line = straight road between two locations (aka two points)

plane = flat ground (the ground cannot have any hills or valleys)

First, let's write some useful definitions:

Point: it is an entity that has a location in a given space or plane, and do not have any surface nor measure.

Line: if we have two points, we can define a line as a straight, infinite ray that connects them. Still does not have a surface

Plane: We can define a plane as a line and a point outside of it, here appears the concept of the surface.

So, the easier one is a plane, a sheet of paper could be a good representation of a plane. And in the same way that a sheet of paper can bend in different ways, also do the planes.

For the line, we could use a really straight wire.

Finally, the point, which is the hardest one to describe (notice that we used points to describe the other two, lines, and planes) so here we could choose something small, that has near to no surface and that also has a location in the space. An example of this could be an electron or any other elemental particle.

If you want to learn more, you can read:

https://brainly.com/question/17213603

Answer:

$3,717

Step-by-step explanation:

Hello, in 1 year there are 12 months.

Let's note I the Initial amount.

So, after 1 month we will get the following, because we compute the interest amount for one month only.

I * ( 1 + 6% * (1/12) )

And the next month, we will have interest of the amount available from previous month so it gives

[tex]I * ( 1+6\% * \dfrac{1}{12} ) * ( 1+6\% * \dfrac{1}{12} ) \\\\=I*(1+\dfrac{6}{12*100})^2\\\\=I*(1+\dfrac{1}{200})^2\\\\=I*(1.005)^2[/tex]

... and after n months ...

[tex]I*(1.005)^n[/tex]

8 years is 8*12 = 96 months. so we are looking for I such that

[tex]I*(1.005)^{96}=6000\\\\<=> I =\dfrac{6000}{1.005^{96}}\\\\=\boxed{3717.14345....}[/tex]

Thank you.

Answer:

(y+10 ) years

Step-by-step explanation:

If Yiadom is y  years now.

Then after 10 years, his anew age will be = (y+10) yrs

Answer:

[tex]P(A\ or\ H) = \frac{4}{13}[/tex]

Step-by-step explanation:

Given

Number of Cards = 52

Required

Determine  the probability of picking a heart or ace

Represent Ace with Ace and Heart = H

In a standard pack of cards; there are

[tex]n(A) = 4[/tex]

[tex]n(H) = 13[/tex]

[tex]n(A\ and\ H) = 1[/tex]

[tex]Total = 52[/tex]

Because the events are non mutually exclusive

[tex]P(A\ or\ H) = P(A) + P(H) - P(A\ and\ H)[/tex]

Where

[tex]P(A) = \frac{n(A)}{Total} = \frac{4}{52}[/tex]

[tex]P(H) = \frac{n(H)}{Total} = \frac{13}{52}[/tex]

[tex]P(A\ and\ H) = \frac{n(A\ and\ H)}{Total} = \frac{1}{52}[/tex]

Substitute these values in the above formula

[tex]P(A\ or\ H) = P(A) + P(H) - P(A\ and\ H)[/tex]

[tex]P(A\ or\ H) = \frac{4}{52} + \frac{13}{52} - \frac{1}{52}[/tex]

Take LCM

[tex]P(A\ or\ H) = \frac{4 + 13 - 1}{52}[/tex]

[tex]P(A\ or\ H) = \frac{16}{52}[/tex]

Reduce fraction to lowest term

[tex]P(A\ or\ H) = \frac{4}{13}[/tex]

Hence, probability of a heart or ace is 4/13

Answer:

0

Step-by-step explanation:

Hello, dividing by 0 is not defined. so

[tex]\dfrac{2x^2}{6x}[/tex]

is defined for x different from 0

This being said, we can simplify by 2x

[tex]\dfrac{2x^2}{6x}=\dfrac{2x*x}{3*2x}=\dfrac{1}{3}x[/tex]

and this last expression is defined for any real number x.

Thank you

Answer:

A. True

Step-by-step explanation:

Stepwise regression is a variable-selection method for independent variables.

Stepwise regression  helps us to recognize and choose the most handy descriptive variables from a list of several reasonable independent variables.

It entails a series of steps that is drafted to locate the most handy X-variable to incorporate in a regression model. During each step of the course of action or method, each X - variable is estimated by applying a set criterion to determine if it is meant to exist in the model.

The basis for selection can be choosing a variable which satisfies the stipulated criterion or removing a variable that least satisfies the criterion. A typical illustration of such criterion is the t value.

Answer: There are 75 books.

Price of each book = $4.

Step-by-step explanation:

Let x = Number of books in the box.

Then as per given,

Cost of x books = $300

Cost of one book = [tex]\$(\dfrac{300}x)[/tex]

Books left after giving 15 of them = x-15

Selling price of (x-15) books=  $330

Selling price of one book = [tex]\$(\dfrac{330}{x-15})[/tex]

Profit on each book= $1.50

Profit = selling price - cost price

[tex]\Rightarrow 1.50=\dfrac{330}{x-15}-\dfrac{300}{x}\\\\\Rightarrow\ 1.50=\dfrac{330(x)-300(x-15)}{x(x-15)}\\\\\Rightarrow\ 1.50=\dfrac{330x-300x+4500}{x^2-15x}\\\\\Rightarrow\ 1.50(x^2-15x)=30x+4500\\\\\Rightarrow\ 1.50x^2-22.5x=30x+4500\\\\\Rightarrow\ 1.50x^2-52.5x-4500=0\\\\\Rightarrow\ 1.50x^2-52.5x-4500=0\\\\\Rightarrow\ x^2-25x-3000=0\ \ [\text{divide by 1.5}][/tex]

[tex]\Rightarrow (x+40)(x-75)=0\\\\\Rightarrow\ x=-40,75[/tex]

Number of books cannot be negative.

So, there are 75 books.

Price of each book = [tex]\dfrac{300}{75}=\$4[/tex]

So price of each book = $4.

Answer:

85.36 far north from the center

10.36 far east from the center

Step-by-step explanation:

The extra direction taken in the north side is x

X/sin(360-315)=50/sin 90

Sin 90= 1

X/sin 45= 50

X= sin45 *50

X= 0.7071*50

X= 35.355 steps

X= 35.36

Then the west direction traveled

West =√(50² - 35.355²)

West = √(2500-1249.6225)

West= √1250.3775

West= 35.36 steps

But this was taken in an opposite west direction

From the center

He is 35.36 +50

= 85.36 far north from the center

And

25-35.36=-10.36

10.36 far east from the center

Answer:

x=9; one ticket is $9

Step-by-step explanation:

4x+12=48

4x=48-12

4x=36

x=36/4

x=9

Work Shown:

Replace x with 3, replace y with -8. Use order of operations PEMDAS to simplify.

x^2 + y^2 + x*y

3^2 + (-8)^2 + 3*(-8)

9 + 64 - 24

73 - 24

49

Answer:

49

Step-by-step explanation:

We are given the polynomial:

[tex]x^2+y^2+xy[/tex]

We want to evaluate when x=3 and y= -8. Therefore, we must substitute 3 for each x and -8 for each y.

[tex](3)^2+(-8)^2+(3*-8)[/tex]

Solve according to PEMDAS: Parentheses, Exponents, Multiplication, Division, Addition, Subtraction

Solve the parentheses first. Multiply 3 and -9.

3*-8=-24

[tex](3)^2+(-8)^2 + -24[/tex]

[tex](3)^2+(-8)^2-24[/tex]

Now, solve the exponents.

3^2= 3*3 =9

[tex]9+ (-8)^2 -24[/tex]

-8^2= -8*-8= 64

[tex]9+64-24[/tex]

Add 9 and 64

[tex]73-24[/tex]

Subtract 24 from 73

[tex]49[/tex]

The polynomial evaluated for x=3 and y= -8 is 49.

Answer:

D no mistakes

Step-by-step explanation:

3+(-4)-7 is equal to 3-4-7=-8

Answer:0

Step-by-step explanation:

3+(-4)-7 when there are parenthesis around a negative number you flip it to positive and then 4+3-7=0

Answer:

63.5

Step-by-step explanation: