please help me guys godbless!​

Complete Question

It is known that a particular laboratory task takes the average person 2.5 seconds (the variance is not known). A researcher was interested in whether older people are slower (take longer) on this task. The researcher tested 30 randomly selected 80-year-olds. Their mean time was 2.7 seconds, with an estimated population standard deviation of 1.4 seconds. What should the researcher conclude? (Use the .05 significance level and use the five steps of hypothesis testing.)

Answer:

The researchers  conclusion is  

   There is no sufficient evidence to show that  older people are slower at the laboratory task    

Step-by-step explanation:

From the question we are told that

   The mean time is  [tex]\mu = 2.5 \ seconds[/tex]

    The sample size is  n  =  30

    The  sample mean is  [tex]\= x = 2.7 \ seconds[/tex]

      The  standard deviation is  [tex]\sigma = 1.4 \ seconds[/tex]

      The level of significance is  [tex]\alpha = 0.05[/tex]

The null hypothesis is  [tex]H_o : \mu = 2.5[/tex]

The alternative hypothesis is  [tex]H_a : \mu > 2.5[/tex]

Generally the test statistics is mathematically represented as

      [tex]z = \frac{\= x - \mu }{ \frac{\sigma}{\sqrt{n} } }[/tex]

=>  [tex]z = \frac{2.7 - 3 }{ \frac{1.4}{\sqrt{30} } }[/tex]

=>  [tex]z =0.78[/tex]

From the z table  the area under the normal curve to the right  corresponding to  [tex]z =0.78[/tex]   is  

        [tex]p-value = P(Z > 0.78) = 0.2177[/tex]

From the value obtained we see that the p-value  > [tex]\alpha[/tex]

   The decision rule is  

Fail to reject the null hypothesis

    The conclusion is  

There is no sufficient evidence to show that the older people are slower at the laboratory task  

Answer:

-239

Step-by-step explanation:

-3(8) 2-6(8)+1

-192-48+1

-240+1

=-239

Answer:

-239

Step-by-step explanation:

Answer:

reflection

Step-by-step explanation:

The correct answer would actually be image... if you need to choose more than one option it could additionally be one of the other options but without a figure it's impossible to tell.

Answer:

"Some irrational numbers are whole numbers" False

"All rational numbers are integers" False

"All integers are whole numbers" False

"No integers are irrational numbers" True

Step-by-step explanation:

I'm 100% sure of this

Answer:

Quadrant I: (⅓, 2⅓)

Quadrant II: (-1⅓, 3⅓)

Quadrant III: (-3, -10) (-3⅓, -1⅓)

Quadrant IV: (9, -1)

Step-by-step explanation:

If it is (+, +), it is in quadrant I.

If it is (-, +), it is in quadrant II.

If it is (-, -), it is in quadrant III.

If it is (+, -), it is in quadrant IV.

Answer:

TRUE

Step-by-step explanation:

i just know it :>

Answer:

[tex]-\frac{3}{2} <x<1[/tex]

Step-by-step explanation:

[tex]2x^{2} +3x-2x-3<0[/tex]

[tex]x(2x+3)-(2x+3)<0\\(2x+3)(x-1)<0\\When 2x+3=0 or x-1=0 \\x= -\frac{3}{2},1[/tex]

[tex]x<-\frac{3}{2} \\-\frac{3}{2} <x<1\\x<1[/tex]

Answer:

x = 27

General Formulas and Concepts:

Pre-Algebra

Algebra I

Step-by-step explanation:

Step 1: Define equation

4x + 10 = 3x + 37

Step 2: Solve for x

Step 3: Check

Plug in x to verify it's a solution.

And we have our final answer!

Answer:

129 [tex](1.3526)^{t}[/tex]

Step-by-step explanation:

Assuming N = [tex]ab^t[/tex]

t = number of years after 2011

N = number of wolves

When  t = 0 , N = 129

129 = [tex]ab^0[/tex]

a = 129

N = 129[tex]b^{t}[/tex]

When t = 2 , N = 236

therefore 236 = 129 [tex]b^{2}[/tex]

[tex]b^{2}[/tex]  = [tex]\frac{236}{129}[/tex]

therefore; b = 1.3526

Answer expressed in the form of a(b)^t.

129 [tex](1.3526)^{t}[/tex]

Answer:

2 its given that cd bisects ab at e so that means e is midpoint of ab

3. vertically opposite angles

4.By SAS congruence

Answer:

B

Step-by-step explanation:

6 2/6 x 1 1/2

(6 x 6) + 2 = 38/6

(1 x 2) + 1 = 3/2

38/6 x 3/2 = 114/12.

114 ÷ 12 = 9 6/12

9 6/12 = 9 3/6 = 9 1/2.

B

Answer:

the answer is b) nine and six twelfths

Step-by-step explanation:

hoped that helped

Answer:

D

Step-by-step explanation:

Answer:

x=10 y=9

Step-by-step explanation:

Answer:

Step-by-step explanation:

surface area of a square pyramid

= Area of base + 1/2 base perimeter * slant height

= (3 x 3) + (1/2 x (3*4) x 5)

= 9 + 30

= 39 km²

Answer:

Answer:

1.11111=111111100000

Showing the work

Rewrite the decimal number as a fraction with 1 in the denominator

1.11111=1.111111

Multiply to remove 5 decimal places. Here, you multiply top and bottom by 105 = 100000

1.111111×100000100000=111111100000

Simplify the improper fraction,

=111111100000

In conclusion,

1.11111=111111100000

Step-by-step explanation:

The fraction equivalent of the repeating decimal 1.11111 is 10/9. This means that 1.11111 is equivalent to 10/9, indicating a ratio of 10 parts to 9 parts. Simplifying the fraction ensures that it is in its simplest form with no common factors between the numerator and the denominator other than 1.

To express the decimal 1.11111 as a fraction, we can use algebraic manipulation. Let's denote the repeating decimal as x:

x = 1.11111...

To eliminate the repeating part, we can multiply x by 10:

10x = 11.11111...

Now, we can subtract the original equation from the multiplied equation to eliminate the repeating part:

10x - x = 11.11111... - 1.11111...

Simplifying the equation:

9x = 10

Dividing both sides by 9:

x = 10/9

Therefore, the fraction equivalent of the repeating decimal 1.11111 is 10/9. This means that 1.11111 is equivalent to 10/9, indicating a ratio of 10 parts to 9 parts. Simplifying the fraction ensures that it is in its simplest form with no common factors between the numerator and the denominator other than 1.

For more details of fraction equivalent of the repeating decimal:

https://brainly.com/question/19473335

#SPJ6

Answer:

[tex][(1+i\sqrt{29}), (1-i\sqrt{29})][/tex], [tex][(1+i\sqrt{26}), (1-i\sqrt{26})][/tex], [tex][(1+i\sqrt{21}), (1-i\sqrt{21})][/tex],

[tex][(1+i\sqrt{14}), (1-i\sqrt{14})][/tex], and [tex][(1+i\sqrt{5}), (1-i\sqrt{5})][/tex].

Step-by-step explanation:

Given that two complex numbers have a product of 30 and the real part of the complex numbers are positive integers.

Let one complex number is [tex]a+ib[/tex] where [tex]a[/tex] is a positive integer and [tex]b[/tex] is a real number.

As the product of two complex numbers is a purely real number, so the other complex number must be the conjugate of the first complex number.

So, another complex number [tex]= a-ib[/tex]

As a product of both the numbers = 30

[tex]\Rightarrow (a+ib)(a-ib)=30 \\\\\Rightarroe a^2 - (ib)^2=30 \\\\\Rightarrow a^2 - (i^2b^2)=30 \\\\Rightarrow a^2 - (-1\times b^2)= 30[/tex] [as i^2=-1]

[tex]\Rightarrow a^2+b^2= 30 \\\\\Rightarrow b^2 = 30-a^2 \\\\[/tex]

[tex]\Rightarrow b=\pm \sqrt {30-a^2} \cdots(i)[/tex]

Now, as a is a positive integer, so by taking possible values of a, we can determine the values of b from the equation (i).

For [tex]a=1[/tex]

[tex]b=\pm \sqrt {30-1^2}=\pm \sqrt {29}[/tex]

The positive sign is for the one number and the negative sign is for the conjugate number (another number).

So, the 1st combination is [tex][(1+i\sqrt{29}), (1-i\sqrt{29})][/tex]

Similarly,

For [tex]a=2[/tex]

[tex]b=\pm \sqrt {30-2^2}=\pm \sqrt {26}[/tex]

So, the 2nd combination is [tex][(1+i\sqrt{26}), (1-i\sqrt{26})][/tex]

For [tex]a=3[/tex]

[tex]b=\pm \sqrt {30-3^2}=\pm \sqrt {21}[/tex]

So, the 3rd combination is [tex][(1+i\sqrt{21}), (1-i\sqrt{21})][/tex]

For [tex]a=4[/tex]

[tex]b=\pm \sqrt {30-4^2}=\pm \sqrt {14}[/tex]

So, the 4th combination is [tex][(1+i\sqrt{14}), (1-i\sqrt{14})][/tex]

For [tex]a=5[/tex]

[tex]b=\pm \sqrt {30-5^2}=\pm \sqrt {5}[/tex]

So, the 5th combination is [tex][(1+i\sqrt{5}), (1-i\sqrt{5})][/tex]

The higher integral value of [tex]a[/tex] is not possible for any real [tex]b[/tex].

Hence, the possible combinations of required numbers are

[tex][(1+i\sqrt{29}), (1-i\sqrt{29})][/tex], [tex][(1+i\sqrt{26}), (1-i\sqrt{26})][/tex], [tex][(1+i\sqrt{21}), (1-i\sqrt{21})][/tex],

[tex][(1+i\sqrt{14}), (1-i\sqrt{14})][/tex], and [tex][(1+i\sqrt{5}), (1-i\sqrt{5})][/tex].

Answer:

B

C and D are already out of the picture since we know lightning is not just light.

Answer:

Build up of electric charges in the clouds (A)

Step-by-step explanation:

Answer:

answer=answer

Step-by-step explanation:

Y E S

I love simple math.

3.25$ to wash the car.

60 seconds: 1 quarter

how many quarters is 3.25?

4 quarters per dollar. so it'd be 13 quarters, then do 13*60=how many seconds u got. 780 seconds. I think you can do 780/60

HINT: hey, psst, it's 13 minutes. : D

HEY DOn'T teLL tHeM tHe ANSWER. :V

Answer:

[tex] y = 2x - 5 [/tex]

Step-by-step explanation:

Find the slope using the points, (1, -3) and (3, 1):

[tex] slope(m) = \frac{y_2 - y_1}{x_2 - x_1} = \frac{1 -(-3)}{3 - 1} = \frac{4}{2} = 2 [/tex]

m = 2

Find the y-intercept (b) by substituting x = 1, y = -3, and m = 2 in [tex] y = mx + b [/tex]

[tex] -3 = (2)(1) + b [/tex]

[tex] -3 = 2 + b [/tex]

Subtract 2 from both sides

[tex] -3 - 2 = 2 + b - 2 [/tex]

[tex] -5 = b [/tex]

[tex] b = -5 [/tex]

Plug in the value of m and b into the slope-intercept form equation, [tex] y = mx + b [/tex].

Thus:

[tex] y = 2x +(-5) [/tex]

✅[tex] y = 2x - 5 [/tex]

Answer:

o.6

Step-by-step explanation:

I think sorry if wrong

Answer:

52 minutes

Step-by-step explanation:

Equation:

[tex]728+23x=0+37x\\728+23x=37x\\728=14x\\x=52[/tex]

So 52 minutes.

Hope this helps plz hit the crown :D

Answer:

Step-by-step explanation:

The rate in this case is slope of the line. The formula of a slope is m = [tex]\frac{y_{2} -y_{1} }{x_{2} -x_{1} }[/tex]  

(10, 325)

(4, 130)

m = [tex]\frac{325-130}{10-4}[/tex] = [tex]\frac{195}{6}[/tex] = 32.5 miles per gallon

The actual rate is less (better) than advertising.

Answer:

yes

Step-by-step explanation:

Answer:

yes

Step-by-step explanation:

1/2=.5 and .5x10=5, 5+3=8 so that proves it is correct.

Answer:

9.5

Step-by-step explanation:

Answer:

D. Ray

Step-by-step explanation:

I just finished the quiz!

Point and line segment are used to define a ray.

A ray is a part of a line that has a fixed starting point but no end point. It can extend infinitely in one direction.

A line extends infinitely in either direction but has no width and is one dimensional. A point is a 0-dimensional mathematical object with a location.

Point and line segment are used to define a ray.

Find out more on ray at: https://brainly.com/question/10404182

Answer:

about 50% of a girl and 50% of a boy

Step-by-step explanation:

I hope this helps

Answer:

Step-by-step explanation:

Answer:

Forty-two (42) of the trees were too small.

Step-by-step explanation:

Find 7/8 of 48.

[tex]\frac{7}{8}[/tex] = 0.875

Multiply the quotient (0.875) by 48 to find [tex]\frac{7}{8}[/tex] of 48.

0.875 × 48 = 42

A. Use the law of cosines:

29² = 34² + c ² - 2•34•c cos(30.3°)

Use a calculator to solve for c ; notice this equation is quadratic, you get two possible solutions, c ≈ 5.973 ≈ 6 or c ≈ 52.738 ≈ 53.

Then use the law of sines to solve for the two possibles measures of angle C :

sin(30.3°)/29 = sin(C )/c

sin(C ) = c sin(30.3°)/29

sin(C ) ≈ 0.1039   or   sin(C ) ≈ 0.9175

C ≈ 6.0°   or   C ≈ 66.6°

The interior angles of any triangle sum to 180°, so the remaining angle has measure either

B = 180° - 30.3° - C

B ≈ 143.7°   or   B ≈ 83.1°

So to recap,

B ≈ 143.7°, C ≈ 6.0°, c ≈ 6

and

B ≈ 83.1°, C ≈ 66.6°, c ≈ 53