1. Đường kính của một loại trục máy là một đại lượng ngẫu nhiên có phân phối chuẩn N (μ = 250mm, σ2 = 25mm2). Trục máy được gọi là hợp quy cách nếu đường kính từ 245mm đến 255mm. Cho máy sản xuất 100 trục. Tính xác suất để:
a. Có 50 trục hợp quy cách.
b. Có không quá 80 trục hợp quy cách

the answer is

10² ( ten square )

step by step :

10² = 10 × 10

= 100

Answer: 100

Step-by-step explanation: 10*10=100

Answer:

25.40

Step-by-step explanation:

tickets  ( 2 at 10.95 each) = 2* 10.95 = 21.90

popcorn ( 1 at 7.50)         = 7.50

Total cost before discount

21.90+7.50=29.40

subtract the discount

29.40-4.00 =25.40

Answer:

Yep! That's correct!

Step-by-step explanation:

We know that Marilyn and her sister are each getting a ticket that cost $10.95. They are also getting a $7.50 popcorn to share. Let's add those values up.

(10.95 * 2) + 7.50 {Multiply 10.95 by 2 to get 21.90.}

21.90 + 7.50 {Add 7.50 to 21.90 to get 29.40}

$29.40 (without the credit) in toal

A credit on a movie reward card functions as a discount, so what we need to do next is subtract 4 from 29.40. That will get us $25.40 as the total cost.

After doing the math, I can deduce that your answer is correct!

Answer:

Ben traveled 93.75% of his usual distance.

Step-by-step explanation:

Given that Ben travels a regular distance of 80 miles to reach office, and today he used an alternative route that covered a distance of only 75 miles, to determine what is the decrease in the percentage of the distance traveled by Ben, the following calculation must be done:

80 = 100

75 = X

75 x 100/80 = X

93.75 = X

Therefore, Ben traveled 93.75% of his usual distance.

Answer:

yes

Step-by-step explanation:

Answer:

Since [tex]np \geq 10[/tex] and [tex]n(1-p) \geq 10[/tex], the normal distribution can be used to approximate the binomial distribution.

The mean is 13.3 and the standard deviation is 3.28.

Step-by-step explanation:

Binomial probability distribution

Probability of exactly x successes on n repeated trials, with p probability.

Can be approximated to a normal distribution, using the expected value and the standard deviation.

The expected value of the binomial distribution is:

[tex]E(X) = np[/tex]

The standard deviation of the binomial distribution is:

[tex]\sqrt{V(X)} = \sqrt{np(1-p)}[/tex]

Normal probability distribution

Problems of normally distributed 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.

When we are approximating a binomial distribution to a normal one, we have that [tex]\mu = E(X)[/tex], [tex]\sigma = \sqrt{V(X)}[/tex], if [tex]np \geq 10[/tex] and [tex]n(1-p) \geq 10[/tex].

The probability than an adult never had the flu is 19%.

This means that [tex]p = 0.19[/tex]

You randomly select 70 adults and ask if he or she ever had the flu.

This means that [tex]n = 70[/tex]

Decide whether you can use the normal distribution to approximate the binomial distribution

[tex]np = 70*0.19 = 13.3 \geq 10[/tex]

[tex]n(1-p) = 70*0.81 = 56.7 \geq 10[/tex]

Since [tex]np \geq 10[/tex] and [tex]n(1-p) \geq 10[/tex], the normal distribution can be used to approximate the binomial distribution.

Mean:

[tex]\mu = E(X) = np = 70*0.19 = 13.3[/tex]

Standard deviation:

[tex]\sigma = \sqrt{V(X)} = \sqrt{np(1-p)} = \sqrt{70*0.19*0.81} = 3.28[/tex]

The mean is 13.3 and the standard deviation is 3.28.

Answer:

462 ways

Step-by-step explanation:

One book never selected means 12 - 1 = 11.

So to find the number of ways, 11C5 which equals to: 11!/(5!(11-5)!) = 462

Answer:

The polynomial is:

[tex]p(x) = -x^3 - 2x^2 + 5x + 6[/tex]

Step-by-step explanation:

Zeros of a function:

Given a polynomial f(x), this polynomial has roots [tex]x_{1}, x_{2}, x_{n}[/tex] such that it can be written as: [tex]a(x - x_{1})*(x - x_{2})*...*(x-x_n)[/tex], in which a is the leading coefficient.

Zeros of −3, −1, and 2

This means that [tex]x_1 = -3, x_2 = -1, x_3 = 2[/tex]. Thus

[tex]p(x) = a(x - x_{1})*(x - x_{2})*(x-x_3)[/tex]

[tex]p(x) = a(x - (-3))*(x - (-1))*(x-2)[/tex]

[tex]p(x) = a(x+3)(x+1)(x-2)[/tex]

[tex]p(x) = a(x^2+4x+3)(x-2)[/tex]

[tex]p(x) = a(x^3+2x^2-5x-6)[/tex]

Passes through the point (1,12).

This means that when [tex]x = 1, p(x) = 12[/tex]. We use this to find a.

[tex]12 = a(1 + 2 - 5 - 6)[/tex]

[tex]-12a = 12[/tex]

[tex]a = -\frac{12}{12}[/tex]

[tex]a = -1[/tex]

Thus

[tex]p(x) = -(x^3+2x^2-5x-6)[/tex]

[tex]p(x) = -x^3 - 2x^2 + 5x + 6[/tex]

9514 1404 393

Answer:

  B(8, 4)

Step-by-step explanation:

Reflection across the origin negates both coordinate values.

  (x, y) ⇒ (-x, -y) . . . . . reflection across the origin

  A(-8, -4) ⇒ B(8, 4)

Answer:

Here are some activities you can do to improve various areas of your intelligence, from reasoning and planning to problem-solving and more.

Memory activities. ...

Executive control activities. ...

Visuospatial reasoning activities. ...

Relational skills. ...

Musical instruments. ...

New languages. ...

Frequent reading. ...

Continued education.

Step-by-step explanation:

Let the husband's income be x

Wife's income be x + 9000

X + X + 9000 = 81000

2X + 9000 – 9000 = 81000 – 9000

2X= 72000

X = 36000

Husband, 36000,

Wife, 9000+36000, 45000

Look at the file, it has every bit of the answer

Answer:

main aapki madad karna chahti hun per Mujhe Ae Jahan question Nahin Aata sorry I don't know

sorry dear friend

Step-by-step explanation:

ok I don't know

Answer:

[tex]g(x) = \frac{3}{x}[/tex]

[tex]g(x) =-\frac{2}{x}[/tex]

[tex]g(x) =\frac{5}{2x}[/tex]

Step-by-step explanation:

Given

[tex]f(x)=\frac{1}{x}[/tex]

Required

Which represents vertical stretch of f(x)

The transformation is represented as:

[tex]g(x) = a* f(x)[/tex]

Where:

[tex]|a| > 1[/tex]

So, the functions are:

[tex]g(x) = \frac{3}{x}[/tex] ---- [tex]|3| > 1[/tex]

[tex]g(x) =-\frac{2}{x}[/tex] --- [tex]|-2|>1[/tex]

[tex]g(x) =\frac{5}{2x}[/tex] --- [tex]|\frac{5}{2}| > 1[/tex]

Answer:

the other person is correct if you need them quick it is a b and d

Step-by-step explanation:

Answer:

x = 38

Step-by-step explanation:

x-13 = 25

Add 13 to each side

x-13+13 = 25+13

x = 38

Check

38-13 = 25

25=25

Answer:

0

Step-by-step explanation:

it says the answer is zero

Answer: 18π

okokok gg

Step-by-step explanation:

Here angle is given in degree.We have convert it into radian.

[tex] {1}^{\circ} =( { \frac{\pi}{180} } )^{c} \\ \therefore \: {80}^{\circ} = ( \frac{80\pi}{180} ) ^{c} = {( \frac{4\pi}{9} })^{c} \: = \theta ^{c} [/tex]

Area of green shaded regions = A

[tex] \sf \: A = \frac{1}{2} { {r}^{2} }{ { \theta}^{ c} } \\ = \frac{1}{2} \times {9}^{2} \times \frac{4\pi}{9} \\ = 18\pi \: {cm}^{2} [/tex]

Answer:

b or a

Step-by-step explanation:

Terms given

No of terms=8

We know

[tex]\boxed{\sf Mean=\dfrac{Sum\;of\:terms}{No\;of\:terms}}[/tex]

[tex]\\ \sf\longmapsto Mean=\dfrac{40+35+32+39+34+35+35+37}{8}[/tex]

[tex]\\ \sf\longmapsto Mean=\dfrac{270}{8}[/tex]

[tex]\\ \sf\longmapsto Mean=35[/tex]

Final Answer:

35

Step-by-step explanation:

-median is the middle number in the data set-

arrange the data set from least to greatest:

40, 30, 32, 39, 34, 35, 35, 37 ⇒ 30, 32, 34, 35, 35, 37, 39, 40

we start from the lowest number and the highest  number and work your way to the middle:

30, 32, 34, 35, 35, 37, 39, 40

notice that there is no middle number:

30, 32, 34, 35, ?, 35, 37, 39, 40

so what we do is add both 35's and then divide it by 2

35 + 35 = 70 ÷ 2 = 35

median: 35

Answer:

6x + 24

Step-by-step explanation:

6 * (4 + x) = 6 * 4 + 6 * x = 6x + 24

Answer:

34

Step-by-step explanation:

let the missing value is x

(25+x) /2 = 29.5

25+x = 29.5(2)

25+x = 59

x = 59-25

x = 34

From the analysis of the discriminant, you obtain that the quadratic function has no real solutions.

In first place, you must know that the roots or solutions of a quadratic function are those values ​​of x for which the expression is 0. This is the values ​​of x such that y = 0. That is, f (x) = 0.

Being the quadratic function f (x)=a*x² + b*x + c, then the solution must be when: 0 =a*x² + b*x + c

The solutions of a quadratic equation can be calculated with the quadratic formula:

[tex]Solutions=\frac{-b+-\sqrt{b^{2} -4*a*c} }{2*a}[/tex]

The discriminant is the part of the quadratic formula under the square root, that is, b² - 4*a*c

The discriminant can be positive, zero or negative and this determines how many solutions (or roots) there are for the given quadratic equation.

If the discriminant:

In this case, a= -40, b=10 and c= -1. Then, replacing in the discriminant expression:

discriminant= 10² -4*(-40)*(-1)

Solving:

discriminant= 100 - 160

discriminant= -60

The discriminant is negative, so the quadratic function has no real solutions.

Answer:

x = 12

Step-by-step explanation:

Missing length of the segment is the altitude of the right triangle.

Based on the geometric mean theorem, we would have the following:

h = √(ab)

Where,

h = x

a = 16

b = 9

Plug in the values:

x = √(16*9)

x = √144

x = 12

Answer:

[tex]\frac{dy}{dt}=304mi/h[/tex]

Step-by-step explanation:

From the question we are told that:

Height of Plane [tex]h=3mi[/tex]

Speed [tex]\frac{dx}{dt}=460mi/h[/tex]

Distance from station [tex]d=4mi[/tex]

Generally the equation for The Pythagoras Theorem is is mathematically given by

[tex]x^2+3^2=y^2[/tex]

For y=d

[tex]x^2+3^2=d^2[/tex]

[tex]x^2+3^2=4^2[/tex]

[tex]x=\sqrt{7}[/tex]

Therefore

[tex]x^2+3^2=y^2[/tex]

Differentiating with respect to time t we have

[tex]2x\frac{dx}{dt}=2y\frac{dy}{dt}[/tex]

[tex]\frac{dy}{dt}=\frac{x}{y}\frac{dx}{dt}[/tex]

[tex]\frac{dy}{dt}=\frac{\sqrt{7}}{4} *460[/tex]

[tex]\frac{dy}{dt}=304.2614008mi/h[/tex]

[tex]\frac{dy}{dt}=304mi/h[/tex]

The identity as been verified/proved as:

[tex]1 - \tan\ a\ tan\ b = 1 - \tan\ a\ tan\ b[/tex]

Given that:

[tex]\frac{\cos(a + b)}{\cos\ a\cos b} = 1 - \tan\ a\ tan\ b[/tex]

Apply cosine identity to the numerator

[tex]\frac{\cos\ a\ cos\ b - \sin a\ sin\ b}{\cos\ a\cos b} = 1 - \tan\ a\ tan\ b[/tex]

Split the fraction:

[tex]\frac{\cos\ a\ cos\ b}{\cos\ a\cos b} - \frac{\sin a\ sin\ b}{\cos\ a\cos b} = 1 - \tan\ a\ tan\ b[/tex]

Cancel out common terms

[tex]1 - \frac{\sin a\ sin\ b}{\cos\ a\cos b} = 1 - \tan\ a\ tan\ b[/tex]

In trigonometry, we have:

[tex]\frac{\sin \theta}{\cos \theta} = \tan \theta[/tex]

So, the equation becomes:

[tex]1 - \tan\ a\ tan\ b = 1 - \tan\ a\ tan\ b[/tex]

Hence, the identity has been verified

Read more about trigonometry identities at:

https://brainly.com/question/21055284

Answer:

only 4 is incorrect...

1,450,000 = 1.45 x [tex]10^{6}[/tex] NOT

1,450,000 = 1.45 x [tex]10^{7\\}[/tex]

Step-by-step explanation:

Answer:

12

Step-by-step explanation:

2²×3

I hope its correct

Answer:

4

[tex] {( - 2 + 1)}^{2} + 5(12 \div 3) - 9 \\ 2 + 1 + 5 \times 4 - 9 \\ 3 + 20 - 9 \\ 23 - 9 \\ 14[/tex]

Answer:

9.6

Step-by-step explanation:

20 divided by 25 = 0.8

Then, 0.8 times 12 = 9.6

I bet that helped! :D

Answer:

Step-by-step explanation: