Would you kindly help me.Im having a hard time understanding and I've been crying a lot trying to understand it ​

Step-by-step explanation:well its basiclly 2-1!

Answer:

B)7

Step-by-step explanation:

2-(-8)=10

10+(-3)=7

Answer:

0.2061 = 20.61% probability, given a class size of 30 students, the average time to complete the test is less than 48.5 minutes

Step-by-step explanation:

To solve this question, we need to understand the normal probability distribution and the central limit theorem.

Normal Probability Distribution

Problems of normal distributions can be solved using the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

Central Limit Theorem

The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].

For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.

Mean of 50 minutes and a standard deviation of 10 minutes.

This means that [tex]\mu = 50, \sigma = 10[/tex]

Class size of 30 students

This means that [tex]n = 30, s = \frac{10}{\sqrt{30}}[/tex]

What is the probability, given a class size of 30 students, the average time to complete the test is less than 48.5 minutes.

This is the p-value of Z when X = 48.5. So

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

By the Central Limit Theorem

[tex]Z = \frac{X - \mu}{s}[/tex]

[tex]Z = \frac{48.5 - 50}{\frac{10}{\sqrt{30}}}[/tex]

[tex]Z = -0.82[/tex]

[tex]Z = -0.82[/tex] has a p-value of 0.2061

0.2061 = 20.61% probability, given a class size of 30 students, the average time to complete the test is less than 48.5 minutes

Answer:

[tex]\boxed{\sf x- intercepts = 0 , 5 \ and \ -4}[/tex]

Step-by-step explanation:

A function is given to us and we need to find the x Intercepts of the graph of the given function . The function is ,

[tex]\sf \implies f(x) = 2x( x - 5 ) ^2(x+4)^3 [/tex]

For finding the x intercept , equate the given function with 0, we have ;

[tex]\sf \implies 2x ( x - 5 )^2(x+4)^3= 0 [/tex]

Equate each factor with 0 ,

[tex]\sf \implies 2x = 0[/tex]

Divide both sides by 2 ,

[tex]\sf \implies\bf x = 0[/tex]

Again ,

[tex]\sf \implies ( x - 5)^2=0 [/tex]

Taking squareroot on both sides,

[tex]\sf \implies x - 5 = 0 [/tex]

Add 5 to both sides,

[tex]\sf \implies \bf x = 5[/tex]

Similarly ,

[tex]\sf \implies \bf x = -4 [/tex]

Hence the x Intercepts are -4 , 0 and 5 .

{ See attachment also for graph } .

9514 1404 393

Answer:

  60

Step-by-step explanation:

The minimum number required is the least common multiple (LCM) of 15 and 4. The numbers 15 and 4 have no common factors, so their LCM is their product.

  15×4 = 60 strands are required

Answer:

0.1667

Step-by-step explanation:

We are given;

Arrival rate, λ = 10 requests per hour

Service rate, μ = 12 requests per hour

From queuing theory, we know that;

ρ = λ/μ

Where ρ is the average proportion of time which the server is occupied.

Thus;

ρ = 10/12

ρ = 0.8333

Now, the probability that no requests for assistance are in the system is same as the probability that the system is idle.

This is given by the Formula;

1 - ρ

probability that no requests for assistance are in the system = 1 - 0.8333 = 0.1667

Answer:

Step-by-step explanation:

8.

any number ×0=0

so b

9.

additive identity

any number+0=same number

c

1.

[tex]\frac{(3+u)^2}{8} =\frac{(3+5)^2}{8} =\frac{8^2}{8} =\frac{64}{8} =8\\where ~u=5[/tex]

2.

-2(a-7)=-2×a-2×(-7)=-2a+14

Step-by-step explanation:

678-72=606/2=303+72=375

Answer:

y=2x-4

Step-by-step explanation:

If you are asking for point slope form, that would be it

Answer:

it's and equilateral triangle because

all sides are equal

Answer:

equilateral triangle i have a math proffesor helping me

Step-by-step explanation:

I have a math proffesor helping me

This is one single number slightly over 17 thousand.

You may need to erase the comma when typing the answer in.

=========================================================

Explanation:

Let's say that another person steps in for Joe, Susan, John, and Meredith. I'll refer to this person as the teacher (perhaps these 9 friends are students on a field trip).

The 9 friends drops to 9-4 = 5 people when those four named people leave the group temporarily. Then it bumps up to 5+1 = 6 people when the teacher steps in. Wherever the teacher is located, the four friends that left will replace the teacher. This guarantees that those four friends stick together.

There are 6! = 6*5*4*3*2*1 = 720 ways to arrange those 6 people. The exclamation mark is a factorial symbol.

Within any of those 720 permutations, we have 4! = 4*3*2*1 = 24 ways to arrange those group of named people when they come back to replace the teacher.

So overall the answer is 4!*6! = 24*720 = 17,280

You may need to erase the comma when typing the answer in.

-------------

Side note: There are 9! = 362,880 ways to arrange all nine friends regardless if those four mentioned people stick together or not. We see that they stick together roughly (17,280)/(362,880) = 0.0476 = 4.76% of the time.

Answer:

a+3b

Step-by-step explanation:

3a+4b-2a-b

=3a-2a+4b-b

=a+3b

Answer:

Step-by-step explanation:

LHS  a - b = -9 - (-6) = -9 +6 = -3

RHS  b-a = -6 - (- 9) =  -6 +9 = 3

as LHS not equal to RHS

a-b not equal to b-a

Thus proven

Answer:

A. $7.00

Step-by-step explanation:

$82-$75=$7.00

Answer:

the answers are on the picture but the numbers may be rounded

Answer:

what is photosynthic ..

p.l.e.a.s.e join eti-fgdd-xjs

why do plant need it

Answer:

Well, divide the shape into rectangles,

triangles or other shapes after that, you can find the area of and then add the areas back together.

Step-by-step explanation:

The area of composite shapes is defined as the area covered by any composite shape. A composite shape is made up of basic shapes put together. Thus, the area of the composite shape is found by individually adding all the basic shapes.

To calculate the area of a composite shape you must divide the shape into rectangles, triangles or other shapes you can find the area of and then add the areas back together.es

Answer:

f(x) = 8x

Explanation:

4 x 2 =8

Answer:

Peter is a-8 in 9 years, (a-8)+ 9+ a+ 9= 76

Answer:

P = 25

A = 33

Step-by-step explanation:

P + 8 = A

P + 9 + A + 9 = 76

P + A = 58

~~~~~~~~~~~~~~

P = 58 - A

P = 58 - P - 8

2 P = 50

P = 25

A = 33

Answer and Explanation:

The irrelevant alternative criterion states that if two candidates A and B contest for an election and candidate B is preferred to candidate A then any other candidate X should not cause candidate A to win the election.

In this case if Mason was candidate A, then candidate B should still win by the majority criterion method and the irrelevant alternative criterion would still be supported. However if he is candidate B then the irrelevant alternative criterion is not supported.

9514 1404 393

Answer:

  25

Step-by-step explanation:

  total books = (books per box) × (number of boxes)

  number of boxes = (total books)/(books per box) = 625 /25 = 25

She needs 25 boxes to move all the books.

Linear pair of angles are supplementary (180°).

So,

(3q) + (15q + 18) = 180°.

Answer:

16 sq units

Step-by-step explanation:

Answer:

(a)[tex]0.15731[/tex]

(b)0.02275

Step-by-step explanation:

We are given that

Mean=0

Standard deviation=0.5 g

True weight of a sample=166 g

Let X denote the normal random variable  with mean =166+0=166

(a)

P(166.5<X<167.5)

=[tex]P(\frac{166.5-166}{0.5}<\frac{X-\mu}{\sigma}<\frac{167.5-166}{0.5})[/tex]

=[tex]P(1<Z<3)[/tex]

=[tex]P(Z<3)-P(Z<1)[/tex]

[tex]=0.99865-0.84134[/tex]

[tex]=0.15731[/tex]

(b)

[tex]P(X>167)=P(Z>\frac{167-166}{0.5})[/tex]

[tex]=P(Z>2)[/tex]

[tex]=1-P(Z<2)[/tex]

[tex]=1-0.97725[/tex]

[tex]=0.02275[/tex]

Answer:

a) The mean number of radioactive atoms that decay per day is 81.485.

b) 0% probability that on a given day, 50 radioactive atoms decayed.

Step-by-step explanation:

Poisson distribution:

In a Poisson distribution, the probability that X represents the number of successes of a random variable is given by the following formula:

[tex]P(X = x) = \frac{e^{-\lambda}*\lambda^{x}}{(x)!}[/tex]

In which

x is the number of sucesses

e = 2.71828 is the Euler number

[tex]\lambda[/tex] is the mean in the given interval.

a. Find the mean number of radioactive atoms that decayed in a day.

29,742 atoms decayed during 365 days, which means that:

[tex]\lambda = \frac{29742}{365} = 81.485[/tex]

The mean number of radioactive atoms that decay per day is 81.485.

b. Find the probability that on a given day, 50 radioactive atoms decayed.

This is P(X = 50). So

[tex]P(X = 50) = \frac{e^{-81.485}*(81.485)^{50}}{(50)!} = 0[/tex]

0% probability that on a given day, 50 radioactive atoms decayed.

9514 1404 393

Answer:

  $150 in 4%, $850 in 6%

Step-by-step explanation:

The fraction that must earn the highest rate is ...

  (5.7 -4.0)/(6.0 -4.0) = 1.7/2 = 0.85

That is 0.85 × $1000 = $850 must be invested at 6%. Matches the last choice.

_____

If you let x represent the amount that must earn 6%, then the total interest earned must be ...

  x·6% +(1000 -x)·4% = 1000·5.7%

  x(6 -4) = 1000(5.7 -4) . . . . . . multiply by 100, subtract 4·1000

  x = 1000·(5.7 -4)/(6 -4) = 850 . . . . as above

Answer:....... no clue ut pls mark me brainiest

Step-by-step explanation:

Answer:

Domain: (-∞, 1]

Range: (-∞, 3]

Step-by-step explanation:

The function starts at point (1, 3) and goes to the left and down forever.

Domain: (-∞, 1]

Range: (-∞, 3]

Answer:

Domain: [tex](-\infty, 1][/tex]

Range: [tex](-\infty, 3][/tex]

Step-by-step explanation:

The domain of a function represents the range of x-values that are part of the function, read left to right. We can see that the function goes forever to the left and stops at [tex]x=1[/tex] when we read left to right. Therefore, the domain of this function is [tex]\boxed{(-\infty, 1]}[/tex].

The point at [tex]x=1[/tex] is a filled-in solid dot so it is included as part of the function. Use square brackets to denote inclusive.

The range of a function represents all y-values that are part of the function, read bottom to top. The function continues down forever and stops at [tex]y=3[/tex] when read bottom to top. Therefore, the range of this function is [tex]\boxed{(-\infty, 3]}[/tex]. Similar to the domain, we use a square bracket on the right to indicate that [tex]y=3[/tex] is included in the function. If the dot was not filled-in, then we would use a parenthesis to indicate that [tex]y=3[/tex] would not be part of the function.

Answer:

48

Step-by-step explanation:

About 40 millions of aluminum cans can be recycled each month in the US. A quarter of these aluminum cans are used to make one aluminum boat. How many aluminum boats can be made in one year in the US?

Given that:

Approximate Number of cans that can be recycled per month in the US = 40 million

Fraction of recycled cans that can be used to make an aluminum boat = 1/4

The number of aluminum boats that can be made in the US in one year :

If about 40 million cans are recycle per month :

The number of boat that can be made from each monthly recycled aluminum cans will be :

Number of monthly recycled can needed to make one boat:

1/4 * 40 million = 10 million cans

Hence, 40,000,000 / 10,000,000 = 4

4 aluminum boats can be made in one month :

Number of months in a year = 12

Number of aluminum boats that can be made in a year :

4 per month * 12 = 48 aluminum boats

Answer:

[tex]X=6.67ft/s[/tex]

Step-by-step explanation:

From the question we are told that:

Height of pole [tex]H_p=15[/tex]

Height  of man [tex]h_m=6ft[/tex]

Speed of Man [tex]\triangle a =4ft/s[/tex]

Distance from pole [tex]d=35ft[/tex]

Let

Distance from pole to man=a

Distance from man to shadow =b

Therefore

 [tex]\frac{a+b}{15}=\frac{b}{6}[/tex]

 [tex]6a+6b=15y[/tex]

 [tex]2a=3b[/tex]

Generally the equation for change in velocity is mathematically given by

 [tex]2(\triangle a)=3(\triangle b )[/tex]

 [tex]2*4=3(\triangle b)[/tex]

 [tex]\triangle a=\frac{8}{3}[/tex]

Since

The speed of the shadow is given as

 [tex]X=\triangle b+\triangle a[/tex]

 [tex]X=4+8/3[/tex]

 [tex]X=6.67ft/s[/tex]