A school authority claims that the average height of students is 178 cm. A researcher has taken a well-designed survey and his sample mean is 177.5 cm and the sample standard deviation is 2. The sample size is 25. Which statement is correct?

a) The result of the survey is statistically significant.

b) The sample mean and population mean is the same.

c) The result of the survey is biased.

d) The difference exists due to chance since the test statistic is small

Answer:V=whl

Step-by-step explanation:

L=Length

W= Width

H= Height

x = a number

7 + 2x = 21

Subtract 7 from both sides

2x = 14

Divide both sides by 2

x = 7

7 is the only number that makes this sentence true.

Answer:

6

Step-by-step explanation:

Rearrange the equation by subtracting what is to the right of the equal sign from both sides of the equation :

                    -2/3*x+9=(4/3*x-3)=?

Step by step solution :

STEP

1

:

           4

Simplify   —

           3

Equation at the end of step

1

:

      2          4

 ((0-(—•x))+9)-((—•x)-3)  = 0  

      3          3

STEP

2

:

Rewriting the whole as an Equivalent Fraction

2.1   Subtracting a whole from a fraction

Rewrite the whole as a fraction using  3  as the denominator :

        3     3 • 3

   3 =  —  =  —————

        1       3  

Equivalent fraction : The fraction thus generated looks different but has the same value as the whole

Common denominator : The equivalent fraction and the other fraction involved in the calculation share the same denominator

Adding fractions that have a common denominator :

2.2       Adding up the two equivalent fractions

Add the two equivalent fractions which now have a common denominator

Combine the numerators together, put the sum or difference over the common denominator then reduce to lowest terms if possible:

4x - (3 • 3)     4x - 9

————————————  =  ——————

     3             3    

Equation at the end of step

2

:

         2                (4x - 9)

 ((0 -  (— • x)) +  9) -  ————————  = 0  

         3                   3    

STEP

3

:

           2

Simplify   —

           3

Equation at the end of step

3

:

         2                (4x - 9)

 ((0 -  (— • x)) +  9) -  ————————  = 0  

         3                   3    

STEP

4

:

Rewriting the whole as an Equivalent Fraction

4.1   Adding a whole to a fraction

Rewrite the whole as a fraction using  3  as the denominator :

        9     9 • 3

   9 =  —  =  —————

        1       3  

Adding fractions that have a common denominator :

4.2       Adding up the two equivalent fractions

-2x + 9 • 3     27 - 2x

———————————  =  ———————

     3             3    

Equation at the end of step

4

:

 (27 - 2x)    (4x - 9)

 ————————— -  ————————  = 0  

     3           3    

STEP

5

:

Adding fractions which have a common denominator

5.1       Adding fractions which have a common denominator

Combine the numerators together, put the sum or difference over the common denominator then reduce to lowest terms if possible:

(27-2x) - ((4x-9))     36 - 6x

——————————————————  =  ———————

        3                 3    

STEP

6

:

Pulling out like terms

6.1     Pull out like factors :

  36 - 6x  =   -6 • (x - 6)  

Equation at the end of step

6

:

 -6 • (x - 6)

 ————————————  = 0  

      3      

STEP

7

:

When a fraction equals zero

7.1    When a fraction equals zero ...

Where a fraction equals zero, its numerator, the part which is above the fraction line, must equal zero.

Now,to get rid of the denominator, then multiplies both sides of the equation by the denominator.

Here's how:

 -6•(x-6)

 ———————— • 3 = 0 • 3

    3    

Now, on the left hand side, the  3  cancels out the denominator, while, on the right hand side, zero times anything is still zero.

The equation now takes the shape :

  -6  •  (x-6)  = 0

Equations which are never true:

7.2      Solve :    -6   =  0

This equation has no solution.

A a non-zero constant never equals zero.

Solving a Single Variable Equation:

7.3      Solve  :    x-6 = 0  

Add  6  to both sides of the equation :  

                     x = 6

One solution was found :

x = 6

Answer:

x=6

Step-by-step explanation:

Answer:

x = 25

∠A = 125

Step-by-step explanation:

∠A = ∠B

where

∠A = 6x + 5°

∠B = 4x + 45°

6x + 5° = 4x + 45°  

6x - 4x = 45 - 5

2x = 40

x = 40/2

x = 20

plugin x into  ∠A = 6x - 5°  

∠A = 6x + 5°

∠A = 6(20) + 5°

∠A = 125

Answer:

x = 25

A = 145

Step-by-step explanation:

Answer: 0.701

Step-by-step explanation:

Formula :  [tex]EBM =z_{\alpha/2}\dfrac{\sigma}{\sqrt{n}}[/tex] , where [tex]\alpha=[/tex] significance level , [tex]\sigma =[/tex] Population standard deviation, n= sample size.

As per given,  n= 22

[tex]\sigma = 2[/tex]

Critical z- value for 90% confidence level : [tex]z_{\alpha/2}=1.645[/tex]

Then,

 [tex]EBM =(1.645)\dfrac{2}{\sqrt{22}}\\\\=(1.645)\dfrac{2}{4.690416}\\\\\approx0.701[/tex]

Hence ,  error bound (EBM) of the confidence interval with a 90% confidence level= ± 0.701

Answer:

Mean = 11.3 grams

Standard Deviation = 3.5 grams

Step-by-step explanation:

Mean is affected by change of origin but standard deviation is not affected. Hence the scale weighed items 1.5 grams affect only the mean not standard deviation. Hence, the mean for new food item is 12.8 - 1.5 = 11.3 grams as weight gain by 1.5 gram due to wrong calibration and the standard deviation remains the same as 3.5 grams.

Answer:

- 73.35

Step-by-step explanation:

-73.35 = -9(8.15)

Hopefully this helps you :)

pls give me brainlest ;)

Answer:

Midpoint = (1,3)

Distance = 10√2

Step-by-step explanation:

Midpoint

[tex]Midpoint = \left(\frac{x_2+x_1}{2},\:\:\frac{y_2+y_1}{2}\right)\\\\\left(x_1,\:y_1\right)=\left(-4,\:8\right),\:\left(x_2,\:y_2\right)=\left(6,\:-2\right)\\\\=\left(\frac{6-4}{2},\:\frac{-2+8}{2}\right)\\\\=(\frac{2}{2} , \frac{6}{2} )\\\\Simplify\\=\left(1,\:3\right)[/tex]

Distance

[tex]Distance = \sqrt{\left(x_2-x_1\right)^2+\left(y_2-y_1\right)^2}\\\\(-4,8)=(x_1,y_1)\\(6,-2)=(x_2,y_2)\\\\d=\sqrt{\left(6-\left(-4\right)\right)^2+\left(-2-8\right)^2}\\\\d = \sqrt{(6+4)^2+(-2-8)^2}\\ \\d = \sqrt{(10)^2 +(-10)^2}\\ \\d = \sqrt{100+100} \\\\d = \sqrt{200}\\ \\d = 10\sqrt{2}[/tex]

Answer:

domain: (-∞, ∞) range: [8, ∞)

hope this helps! ;)

Step-by-step explanation:

Answer:

y=9x

It's 9x because for every hour he earns 9 dollars.

Answer:

x<_2

Step-by-step explanation:

first off solve this like a regular equation the >_ dosent matter till later

so basically first multiply - by 13 and -x so you get -13 and x (multiplying two negatives = a positive)

so its 5x-13+x>_9x-7

add 5x and x to get 6x-13 on one side

then you get 6x-13>_9x-7 then subtract -9x from both sides

so its now -3x-13>_-7 add 13 so you get -3x>_6

then divide both sides by -3 (when you divide an equation with a >< or <_ >_ by a negative number that sign switches) so it will now be x<_2

that your final answer hope this helps :)

Answer: maggie is right

Step-by-step explanation:

because the first number is 7 and the first number in the sentence is 7

Answer:

30 ft

Step-by-step explanation:

10 yards x 3 ft per yard= 10x3=30 ft

Answer:

512(cm)3

Step-by-step explanation:

Step-by-step explanation:

Answer:

12,10,2

Step-by-step explanation:

Answer:

-9/14 so the answer is B

Step-by-step explanation:

Hope this helps!!!

Answer:

d= 4t

Step-by-step explanation:

to find distance, the equation is speed multiplied by time and in this question we are given the time and distance so we have to divide 9km by 2.25hrs to find the speed: 9÷2.25= 4 so, the equation would be d=4t which means that to find distance we need to multiply 4 by the time.

[tex]\text{Hello!}[/tex]

[tex]\boxed{y = 6x}[/tex]

[tex]\text{Given equation:}\\x + 6y = 6\\\\\text{Rewrite the equation in the form y = mx + b to find the slope:}\\\\x + 6y = 6\\\\6y = -x + 6\\\\\\\text{Divide all terms by 6:}\\y = -x/6 + 1\\\\\text{Remember that a perpendicular line contains aslope of the negative reciprocal, therefore:}\\\\-1/6x \text{ becomes } 6\\\\\text{Use the coordinates given to find the equation of the perpendicular line:}\\\\(-6) = 6(-1) + b\\\\\\-6 = -6 + b\\\\b = 0\\\\\text{Therefore, the equation is:}[/tex]

[tex]\boxed{y = 6x}[/tex]

Answer:

y=6x

Step-by-step explanation:

honestly i guessed and got it rigth

Answer:

Y=-5

X=6

Step-by-step explanation:

set x =0 then solve then set y=o and solve

Answer:

5x - 6y = 30

6y = 5x - 30

Y = 5/6x - 5

y intercept = -5

Therefore (0, -5)

0 = 5/6x - 5

5/6x = 5

x = 6

x intercept = 6

therefore (6,0)

answer : The x-intercept is (6, 0), the y-intercept is (0, –5).

x intercept =

Answer:

it is d

Step-by-step explanation: make me brainliest

Answer:

4 units left

explanation: the [x-4] part in the equation is the only part with a know value and with a negative x we know it will be going to left of the 0 on the number line

Answer:

no solution

Step-by-step explanation:

Answer:

1x.

..................................

hope it will works

..................................

Answer:

Q1.

Perimeter = 2(Length + Width)

Perimeter = [tex]2((2x-7)+(x^2-5))[/tex]

[tex]2\left(2x-7\right)+2\left(x^2-5\right)[/tex]

[tex]4x-14+2x^2-10[/tex]

[tex]2x^2+4x-24[/tex]

Q2.

[tex](-9x^2+3x-10)-(-15x^2-5x+11)[/tex]

[tex]-9x^2+3x-10+15x^2+5x-11[/tex]

[tex]6x^2+8x-21[/tex]

Answer:

45

Step-by-step explanation:

Answer:

45 square units

Step-by-step explanation:

Answer:

b + 5

Step-by-step explanation:

If there are 5 more girls and b represents boys, then adding 5 to b (boys) gives you the number of girls. Hope this helps!

Answer:

The second one

Step-by-step explanation: 27-5=22 then u divide 22 divided by 2 and you get 11 then you add five girls to the 11 and you get 16 so there's 11 boys and 16 girls at the party which makes the equation 11+5=16 so the answer is number b (the second one).

Answer: yes the answer is $6.49!!

Step-by-step explanation:

all you have to do is multiply the money amounts by the item count, add both answers, and you get the sum!! Noice Job!!

Answer:

x > −4

Step-by-step explanation:

Step 1: Simplify both sides of the inequality.

3x+24>12

Step 2: Subtract 24 from both sides.

3x+24−24>12−24

3x>−12

Step 3: Divide both sides by 3.

3x/3 > −12/3

x>−4

Answer:

x>−4

Hope this helps

Answer:

sine(?)=opposite/hypotenuse

sine(?)=2/8

sine(?)=0.25

sine inverse of 0.25

angle?=14.48°

Answer:

14° (nearest degree)

Step-by-step explanation:

Please see the attached picture for full solution.

The variable is the letter like x or y. The coefficient is the number next to the variable like the 2 in 2x or if its just x it would be 1. The constant is the number by itself usually at the end.

Example 2x+5

Variable is x constant is 5 and coefficient is 2. Sorry i didn't answer the actual question and just told you how to find it but those expressions don't have any of these things.

Answer:

-1 and 1/3

Step-by-step explanation:

I replaced each variable with 1. Other than that I just guessed and got it right lol

Answer:

[tex]P(X_s^c|X_F) =0.2[/tex]

[tex]P(X_s^c|X_F) =0.31[/tex]

[tex]P(X_s^c|X_F) =0.331[/tex]

Step-by-step explanation:

From the given information:

Let represent [tex]X_F[/tex] as the first player getting an ace

Let [tex]X_S[/tex] to be the second player getting an ace and

[tex]\sim X_S[/tex] as the second player not getting an ace.

So;

The probabiility of the second player not getting an ace  and the first player getting an ace can be computed as;

[tex]P(\sim X_S| X_F) = 1 - P(X_S|X_F)[/tex]

[tex]P(X_S|X_F) = \dfrac{P(X_SX_F)}{P(X_F)}[/tex]

Let's determine the probability of getting an ace in the first player

i.e

[tex]P(X_F) = 1 - P(X_F^c)[/tex]

[tex]= 1 -\dfrac{(^{2n-2}_n)}{(^{2n}_n)}}[/tex]

[tex]= 1 - \dfrac{n-1}{2(2n-1)}[/tex]

[tex]= \dfrac{3n-1}{4n-2} --- (1)[/tex]

To determine the probability of the second player getting an ace and the first player getting an ace.

[tex]P(X_sX_F) = \text{ (distribute aces to both ) and (select the left over n-1 cards from 2n-2 cards}[/tex][tex]P(X_sX_F) = \dfrac{2(^{2n-2}C_{n-1})}{^{2n}C_n}[/tex]

[tex]P(X_sX_F) = \dfrac{n}{2n -1}---(2)[/tex]

[tex]P(X_s|X_F) = \dfrac{2}{1}[/tex]

[tex]P(X_s|X_F) = \dfrac{2n}{3n -1}[/tex]

Thus, the conditional probability that the second player has no aces, provided that the first player declares affirmative is:

[tex]P(X_s^c|X_F) = 1- \dfrac{2n}{3n -1}[/tex]

[tex]P(X_s^c|X_F) = \dfrac{n-1}{3n -1}[/tex]

Therefore;

for n= 2

[tex]P(X_s^c|X_F) = \dfrac{2-1}{3(2) -1}[/tex]

[tex]P(X_s^c|X_F) = \dfrac{1}{6 -1}[/tex]

[tex]P(X_s^c|X_F) = \dfrac{1}{5}[/tex]

[tex]P(X_s^c|X_F) =0.2[/tex]

for n= 10

[tex]P(X_s^c|X_F) = \dfrac{10-1}{3(10) -1}[/tex]

[tex]P(X_s^c|X_F) = \dfrac{9}{30 -1}[/tex]

[tex]P(X_s^c|X_F) = \dfrac{9}{29}[/tex]

[tex]P(X_s^c|X_F) =0.31[/tex]

for n = 100

[tex]P(X_s^c|X_F) = \dfrac{100-1}{3(100) -1}[/tex]

[tex]P(X_s^c|X_F) = \dfrac{99}{300 -1}[/tex]

[tex]P(X_s^c|X_F) = \dfrac{99}{299}[/tex]

[tex]P(X_s^c|X_F) =0.331[/tex]

Answer:

-9.4 degree Celsius

Step-by-step explanation:

By using the formula = 15F - 32 × 5/9

= -9.4 degree Celsius