Pls Help..... 50 points and brainliest if you answer correctly!

if you  would've payed attention you wouldn't ask brainly-

Answer:

Step-by-step explanation:

Expression given → 4 - 9x + 21

Chang's expression → 4 - 3(3x + 7)

Chang's expression is incorrect because the correct expression is [4 - 3(3x - 7)]

Benjamin's expression → 4 + 3(3x + 7)

Benjamin's expression is incorrect because the correct expression is [4 - 3(3x - 7)]

Habib's expression → 4 + 12x

Habib's expression is incorrect because the correct expression is [4 - 3(3x - 7)]

Correct expression → [4 - 3(3x - 7)]

Answer:

1.- CI = 94% (  μ₀ -  1,04   <  x   <   μ₀ +  1,04 )

2.- CI = 98 % ( μ₀ - 2,05  <  x   <   μ₀ + 2,05 )

3.- CI = 96 %  (  μ₀ - 1,75  <  x   <   μ₀  + 1,75 )

Step-by-step explanation:

Sample size      n  = 3000000

Sample mean   x  =  200

Standard deviation   s  =  30

From  z-table values of z(c):

CI  94 %        Confidencial level   α = 6 %   α = 0,06   z(c) = 1,55

CI  98 %        Confidencial level   α = 2 %   α = 0,02   z(c) = 2,05

CI  96 %        Confidencial level   α = 4 %   α = 0,04   z(c) =  1,75

MOE = z(c) * σ/√n

1.-MOE =  1,55* 30 / √2000    MOE = 1,04

2.-MOE = 2,05*30/√2000      MOE = 1,38

3.-MOE = 1,75*30/√2000        MOE = 1,17

Then CI

1.-  CI = 94 %     (  μ₀ -  MOE <  x  <   μ₀ -  MOE )

     CI  =  (  μ₀ -  1,04   <  x   <   μ₀ +  1,04 )

2.-CI = 98 %

     CI  = (    μ₀ - 2,05  <  x   <   μ₀ + 2,05 )

3.- CI = 96 %

     CI = (  μ₀ - 1,75  <  x   <   μ₀  + 1,75 )

Using the t-distribution, it is found that:

We are given the standard deviation for the sample, which is why the t-distribution is used to solve this question.

The information given is:

The interval is:

[tex]\overline{x} \pm t\frac{s}{\sqrt{n}}[/tex]

Considering a 94% confidence level, using a calculator, with 200 - 1 = 199 df, the critical value is t = 1.8916, hence:

[tex]\overline{x} - t\frac{s}{\sqrt{n}} = 200 - 1.8916\frac{30}{\sqrt{2000}} = 198.73[/tex]

[tex]\overline{x} + t\frac{s}{\sqrt{n}} = 200 + 1.8916\frac{30}{\sqrt{2000}} = 201.27[/tex]

The 94% confidence interval is (198.73, 201.27).

Considering a 96% confidence level, using a calculator, with 200 - 1 = 199 df, the critical value is t = 2.0673, hence:

[tex]\overline{x} - t\frac{s}{\sqrt{n}} = 200 - 2.0673\frac{30}{\sqrt{2000}} = 198.61[/tex]

[tex]\overline{x} + t\frac{s}{\sqrt{n}} = 200 + 2.0673\frac{30}{\sqrt{2000}} = 201.39[/tex]

The 96% confidence interval is (198.61, 201.39).

Considering a 98% confidence level, using a calculator, with 200 - 1 = 199 df, the critical value is t = 2.3452, hence:

[tex]\overline{x} - t\frac{s}{\sqrt{n}} = 200 - 2.3452\frac{30}{\sqrt{2000}} = 198.43[/tex]

[tex]\overline{x} + t\frac{s}{\sqrt{n}} = 200 + 2.3452\frac{30}{\sqrt{2000}} = 201.57[/tex]

The 98% confidence interval is (198.43, 201.57).

You can learn more about the use of the t-distribution to build a confidence interval at https://brainly.com/question/16162795

Answer: h>-39

Step-by-step explanation:

Step-by-step explanation:

7 [tex]\frac{1}{2}[/tex] ÷ 2

A. 2 × ? = 7[tex]\frac{1}{2}[/tex]

   Divide 2 on both sides to bring all the constants on one side...

   ? = 7 1/2 ÷ 2

B. 7 1/2 x ? = 2

  Divide 7 1/2 on both sides to isolate the ?

  ? = 2 ÷ 7 1/2

C. 2 x 7 1/2

    You already know that the initial problem is asking for an answer that is half of 7 1/2 not twice 7 1/2

D. ? x 7 1/2 = 2

   Divide 7 1/2 on both sides

    ? = 2÷ 7 1/2

E. It's basically the same thing as A

Whatever is bolded is the answer

I hope this made sense and I hope this helps!!!

Answer:

80

Step-by-step explanation:

Just use 2,400 / 30 to solve. The answer should be 80:

Therefore, 2,400 / 80 = 30

Hope this helps :)

Answer:

[tex]y = 2.25x \\ \boxed{y = \frac{9}{4} x}[/tex]

Coordinates :---

• (x, y)

→(-2, -9/2)

→(-1, -9/4)

→(0, 0)

→(1, 9/4)

→(2, 9/2)

Answer:

chocolate= 180 students

vanilla= 120

strawberry= 210

mango= 210

Step-by-step explanation:

The chocolate section of the pie chart is at a right angle (90 degrees), which means a quarter of the students prefer chocolate

720/4= 180

The vanilla section is 60 degrees which is 2/3 of 90

180/3=60

60x2=120

the mango and strawberry sections represent whats left which is 420 students. The sections are equal to each other so they're each 210 students

Answer:

$41.6

Step-by-step explanation:

20/100 x 52 = 10.4

52 - 10.4 = 41.6

Answer:

See answer below

Step-by-step explanation:

There is NO elementary function that gives the antiderivative of e^(-x^2)

This expression in fact is called the Gaussian integral, since it gives the Gaussian bell curve.

Its integration is done by numerical methods, it is widely used in Statistics, and there are tables to calculate definite integrals associated with probability distributions.

Answer:

Step-by-step explanation:

92

Answer:

x > 4

Step-by-step explanation:

Answer:

x = 4

Step-by-step explanation:

Answer:

1) m ∠B = 132°

2) m ∠B = 113°

Step-by-step explanation:

1. In triangle ABC, m ∠A=36, and m ∠C=12. Calculate m ∠B.

We are given measure of 2 angles and we need to find the third angle.

We know that, sum of angles of triangle = 180°

We can write as:

∠A + ∠B + ∠C = 180°

Now put m ∠A=36 and m ∠C=12, to find m ∠B

[tex]\angle A + \angle B + \angle C = 180\\36+ \angle B +12=180\\\angle B+48=180\\\angle B=180-48\\\angle B=132[/tex]

So, we get m ∠B = 132°

2. In triangle ABC, m ∠A=40, and m ∠C=27. Calculate m ∠B.

We are given measure of 2 angles and we need to find the third angle.

We know that, sum of angles of triangle = 180°

We can write as:

∠A + ∠B + ∠C = 180°

Now put m ∠A=40 and m ∠C=27, to find m ∠B

[tex]\angle A + \angle B + \angle C = 180\\40+ \angle B +27=180\\\angle B+67=180\\\angle B=180-67\\\angle B=113[/tex]

So, we get m ∠B = 113°

Answer:43.1 km/h

Step-by-step explanation:

Suppose velocity of motorist [tex]\vec{v_1}=50\hat{j}[/tex]

The appeared velocity of wind or resultant velocity is [tex]\vec{v_r}=60[\hat{i}\cdot \frac{1}{\sqrt{2}}+\hat{j}\cdot \frac{1}{\sqrt{2}}][/tex]

Suppose the true velocity of wind is [tex]v_2[/tex]

so, [tex]\vec{v_1}+\vec{v_2}=\vec{v_r}[/tex]

[tex]\vec{v_2}=\frac{60}{\sqrt{2}}\hat{i}+(\frac{60}{\sqrt{2}}-50)\hat{j}\\\vec{v_2}=42.42\hat{i}-7.57\hat{j}\\absolute\ velocity=\sqrt{42.42^2+(-7.57)2}=43.09\approx 43.1\ km/h[/tex]

Answer:

(y+5)^2=-3/4(x+1)

Step-by-step explanation:

Step-by-step explanation:

ans:7*(-(3-5))..........

Answer:

Its either C or D but i think its D

Step-by-step explanation:

Answer:

false

Step-by-step explanation:

Answer:

the answer is C. y=3x-4

Step-by-step explanation:

the slope can be found by taking two points and putting them in this equation:

[tex]\frac{y_{2}-y_{1} }{x_{2}- x_{1} }[/tex]

so using the first two points, the equation would be

[tex]\frac{2-(-1) }{2-1}[/tex]

giving you 3 for the slope

the y-intercept (where x=0) is found by subtracting 3 from -1 which is -4.

Answer:

11 1/2   or    23/2

Step-by-step explanation:

K = 10 + 3/2 = 10 + 1 + 1/2

Answer:

L x W (original)

(L+3) x w     (one dimension changed)

(L+3)(W+3)   (both dimensions changed)  

Step-by-step explanation:

Rectangle when one dimension increase 3 units, area will change from original (L and w are its two sides)

L x W to (L+3) x w

If both dimension increase 3 units, the area will become

(L+3)(W+3)

Answer:

72

Step-by-step explanation:

Given that:

P(Red) = Probability of randomly choosing a red

Probability of randomly choosing a red = 7/12

Number of red marbles = 42

The number of marbles in the bag :

P(Red) = number of red marbles / total number of marbles

Total number of marbles = (red marbles + blue marbles)

P(red) = 7/ 12 ;number of red = 42

P(Red) = number of red marbles / total number of marbles

Let:

x = total number of marbles

7/12 = 42 / x

(7/ 12)x = 42

7x / 12 = 42

7x = 12 * 42

7x = 504

x = 504 / 7

x = 72

Answer:

17 1/3 pounds

Step-by-step explanation:

6 1/2=6.5

6.5×2=13

6.5×2/3=4.3333333333

13+4.33=17.33=17 1/3

So the larger dog weighs 17 1/3 pounds

Please give brainliest, thank me and rate it 5 if this helped you.

Answer:The larger dog weighs 17 1/3 pounds .

Step-by-step explanation:6 1/2 ×  2 2/3

                                           = 13/2 ×   8/3

                                         = 104 /6  

                                         = 52/3

                                       = 17 1/3

That is how you solve it and the steps you do to get to the answer.

But now I will explain.So the first step is you change 6 1/2 and 2 2/3 into a improper fraction which 6 1/2 as an improper fraction is 13/2 and 2 2/3 as an improper fraction is 8/3 .The next  step is you multiply the improper fractions together which are 13/2 multiply 8/3 which you get 104/6.After that you simplify 104/6 ,and you get 52/3 . You divided both 104 and 6 (104/6) by 2 which gives you 52/3. (104 ÷ 2  /6 ÷ 2 =52/3) Lastly you change 52/3 which is a improper fraction into a mixed number which gives you 17 1/3 as your answer.

I hope this helps :)

Please give brainliest if it helps .Thanks :)

Answer: 2/5y and -.2y are like terms, and -6 and -2 are like terms

Step-by-step explanation:

Answer:

Hey! Seems like you already have an answer but I am going to tell you why it's your answer!

Step-by-step explanation:

So 2/5y and 0.2y are like terms because they both have a letter at the end are a variable. Now -6 and -2 or both negative numbers so what you're looking out for or matching sign's like the one's I put above hope this helps a bit!!! Good Luck!!!!

Answer:

x = 13

Step-by-step explanation:

m∠ABC + m∠CBD = 180°       {linear pair}

3x + 43 + 6x +  20 = 180

3x + 6x + 43 + 20 = 180

    9x  + 63           = 180

                     9x = 180 - 63

                    9x = 117

                     x = 117/9

x = 13

Answer:

Ima just steal the points

Step-by-step explanation: