The length of time, in hours, it takes a group of people, 40 years and older, to play one soccer match is normally distributed with a mean of 2 hours and a standard deviation of 0.5 hours. A sample of size 50 is drawn randomly from the population. Find the probability that the sample mean is less than 2.3 hours. g

Answer:

c = 11.3 mi/h

Step-by-step explanation:

Since Square has all of the same sides, hence bobs speed will be the same for all of the sides.

All of the sides are equal in a square

=> Let's consider the two sides along with the diagonal a right angled triangle

=> [tex]c^2 = a^2 + b^2[/tex]

Where c is the speed of Rob along the diagonal and b and c is the speed of Bob along the side

=> [tex]c^2 = 8^2+8^2[/tex]

=> [tex]c^2 = 64+64[/tex]

=> [tex]c^2 = 128\\[/tex]

Taking sq root on both sides

=> c = 11.3 mi/h

Answer:

x4+7x+3

Step-by-step explanation:

Answer:

301.44

Step-by-step explanation:

V=π r² h

V=π (4)² (12)

V= 603.19

divide by 2 to find half full: ≈ 301

301.44

Answer:

(67/10)x + 9 (answer [2])

Step-by-step explanation:

3(7/5x + 4) - 2(3/2 - 5/4x). after the indicated multiplication has been carried out, is:

(21/5)x + 12 - 3 + (5/2)x

Combining like terms, we get (4.2 + 2.5)x + 9, or

6.7x + 9, or (67/10)x + 9 (answer [2])

Answer:

D. The statement is false. Double blinding is used to decrease the placebo effect.

Step-by-step explanation:

In a double blind study, neither researchers nor the participants know which group is receiving the placebo. If the researchers do not know which group took the medication, they cannot influence the behavior of this group, knowingly or nor, by suggesting how they should behave.

Therefore, a​ double-blind experiment is used to decrease the placebo effect.

Answer:

-4

Step-by-step explanation:

The slope would be (5 - (-3)) / (2 - 4) = 8 / -2 = -4.

Answer:

[tex]\huge\boxed{\text{The slope}\ m=-4}[/tex]

Step-by-step explanation:

The formula of a slope:

[tex]m=\dfrac{y_2-y_1}{x_2-x_1}[/tex]

(x₁; y₁), (x₂; y₂) - points on a line

We have the points:

[tex](2;\ 5)\to x_1=2;\ y_1=5\\(4;\ -3)\to x_2=4;\ y_2=-3[/tex]

Substitute:

[tex]m=\dfrac{-3-5}{4-2}=\dfrac{-8}{2}=-4[/tex]

so you have the amount.

amount: 1200

then you have the ratio

ratio: 3:5

you have the count.

count: 2

and then you have the shares

shares: 8

and the amount per share is 150.00

so the total amount of shares is the sum of each person's ratio so,

so 1:5:2:3:9 = 1 + 5 + 2 + 3 +9 = 20 shares.  hope that helps you..

Answer:

z < 4

Step-by-step explanation:

2(3z-4) < 16

Divide by 2 on both sides

3z-4 < 8

Add 4 to both sides

3z < 12

Divide by 3 on both sides

z < 4

________________________Alike______________________

→ Both of the lines are proportional meaning they go through the origin.

→ Both of the lines have a positive slope meaning the slope goes towards the top right corner.

__________________________________________________

_____________________Difference_____________________

→ The 2 lines have different slopes, the first one has a slope of 1/3x whereas the 2nd one has a slope of 3x.

→ The points that create the lines are totally different, no two points are the same.

__________________________________________________

Answer:

think its 3a 3.83838

Step-by-step explanation:

Answer:

-23/11

Step-by-step explanation:

Answer:

The cost of printing 142 more posters when 18 has already been printed is $5.57.

Step-by-step explanation:

We are given that the marginal cost (dollars) of printing a poster when x posters have been printed is given by the following equation C'(x)=x^-3/4.

The given equation is: [tex]C'(x) = x^{\frac{-3}{4} }[/tex]

The cost of printing 142 more posters when 18 have already been printed is given by;

Integrating both sides of the equation and using the limits we get;

[tex]\int_{a}^{b} C'(x) dx=\int_{18}^{142} x^{\frac{-3}{4}}dx[/tex]

As we know that  [tex]\int\limits {x}^{n} \, dx = \frac{x^{n+1} }{n+1}[/tex] , so;

          =  [tex]\frac{x^{\frac{-3}{4}+1 } }{\frac{-3}{4}+1 } ]^{142} __1_8[/tex]

          =  [tex]\frac{x^{\frac{1}{4} } }{\frac{1}{4} } ]^{142} __1_8[/tex]

          =  [tex]4[x^{\frac{1}{4} } } ]^{142} __1_8[/tex]

          =  [tex]4[(142)^{\frac{1}{4} }- (18)^{\frac{1}{4} }} ][/tex]

          =  $5.57

Hence, the cost of printing 142 more posters when 18 has already been printed is $5.57.

Answer:

The speed of the jet is 347 mph and the  speed of the wind is 18 mph.

Step-by-step explanation:

We have the following:

x = the speed of the jet in still air.

y = the speed of the wind

we know that the speed is equal to:

v = d / t

therefore the distance would be:

d = v * t

if we replace with the information of the exercise we have:

3 * (x + y) = 1095

3 * (x - y) = 987

we must solve this system of equations, add both equations and we are left:

3 * x + 3 * y = 1095

3 * x - 3 * y = 987

3 * x + 3 * y + 3 * x - 3 * y = 1095 + 987

6 * x = 2082

x = 2082/6 = 347

now to calculate y, we replace:

3 * (347 + y) = 1095

1041 + 3 * y = 1095

3 * y = 1095 - 1041

y = 54/3 = 18

The speed of the jet is 347 mph and the  speed of the wind is 18 mph.

Answer:

13

Step-by-step explanation:

The range of a set of data is the difference between the highest and lowest values in the set.

So, in order to find the range, you first order the data from least to greatest. Which it is already.

3, 7, 11, 14, 16

Then subtract the smallest value from the largest value in the set.

16 - 3 = 13

Hope this helps you out! : )

Answer:

Step-by-step explanation:

Given,

a = 4

y = -6

Now,

[tex] - a + 3y[/tex]

Plug the values

[tex] = - 4 + 3 \times ( - 6)[/tex]

Multiply the numbers

[tex] = - 4 + ( - 18)[/tex]

When there is a (+) in front of an expression in parentheses, the expression remains the same.

[tex] = - 4 - 18[/tex]

Calculate

[tex] = - 22[/tex]

Hope this helps..

Best regards!!

Answer:

14

Step-by-step explanation:

-4 + 3(6)

-4+18

14

Answer:

C. x = 2

Step-by-step explanation:

[tex] \sqrt{9x + 7} + \sqrt{2x} = 7 [/tex]

Since you have square roots, you need to separate the square roots and square both sides.

[tex] \sqrt{9x + 7} = 7 - \sqrt{2x} [/tex]

Now that one square root is on each side of the equal sign, we square both sides.

[tex] (\sqrt{9x + 7})^2 = (7 - \sqrt{2x})^2 [/tex]

[tex] 9x + 7 = 49 - 14\sqrt{2x} + 2x [/tex]

Now we isolate the square root and square both sides again.

[tex] 7x - 42 = -14\sqrt{2x} [/tex]

Every coefficient is a multiple of 7, so to work with smaller numbers, we divide both sides by 7.

[tex] x - 6 = -2\sqrt{2x} [/tex]

Square both sides.

[tex] (x - 6)^2 = (-2\sqrt{2x})^2 [/tex]

[tex] x^2 - 12x + 36 = 4(2x) [/tex]

[tex] x^2 - 20x + 36 = 0 [/tex]

We need to try to factor the left side.

-2 * (-18) = 36 & -2 + (-18) = -20, so we use -2 and -18.

[tex] (x - 2)(x - 18) = 0 [/tex]

[tex] x = 2 [/tex]   or   [tex] x = 18 [/tex]

Since solving this equation involved the method of squaring both sides, we much check for extraneous solutions by testing our two solutions in the original equation.

Test x = 2:

[tex] \sqrt{9x + 7} + \sqrt{2x} = 7 [/tex]

[tex] \sqrt{9(2) + 7} + \sqrt{2(2)} = 7 [/tex]

[tex] \sqrt{25} + \sqrt{4} = 7 [/tex]

[tex] 5 + 2 = 7 [/tex]

[tex] 5 = 5 [/tex]

We have a true equation, so x = 2 is a true solution of the original equation.

Now we test x = 18.

[tex] \sqrt{9x + 7} + \sqrt{2x} = 7 [/tex]

[tex] \sqrt{9(18) + 7} + \sqrt{2(18)} = 7 [/tex]

[tex] \sqrt{162 + 7} + \sqrt{36} = 7 [/tex]

[tex] \sqrt{169} + 6 = 7 [/tex]

[tex] 13 + 6 = 7 [/tex]

[tex] 19 = 7 [/tex]

Since 19 = 7 is a false equation, x = 18 is not a true solution of the original equation and is discarded as an extraneous solution.

Answer: C. x = 2

Answer:

[tex]5.625\pi[/tex] m³.

Step-by-step explanation:

The volume of a cylinder is found by calculating pi * r^2 * h.

In this case, h = 2.5, and r = 1.5.

pi * 1.5^2 * 2.5

= pi * 2.25 * 2.5

= pi * 5.625

So, the exact volume of the cylinder is [tex]5.625\pi[/tex] m³.

Hope this helps!

Answer: Volume of Cylinder: [tex]\pi r^{2} *h[/tex]

               5.625π  m.

Step-by-step explanation:

[tex]\pi r^{2} *h[/tex]   Cylinder Area Formula

[tex]\pi *1.5^{2} *2.5[/tex]   Substitution

[tex]\pi * 2.25 *2.5[/tex]   Exponent

[tex]\pi *5.625[/tex]   Multiply

[tex]5.625\pi[/tex] Answer

Answer:

sec B = 17 / 15

Step-by-step explanation:

Sec theta = hyp / adj

sec B = 17 / 15

Answer:

17/15

Step-by-step explanation:

The secant of an angle is the ratio of the hypotenuse to the adjacent angle (it is also the reciprocal of cosine).

secθ=hypotenuse/adjacent

sec(∠B)= hypotenuse/adjacent

The hypotenuse in this triangle is 17, because it is opposite the right angle or the little square.

sec(∠B)=17/adjacent

The side adjacent, or next to angle B is 15.

sec(∠B)= 17/15

This fraction cannot be reduced further, therefore the secant of angle B is 17/15.

Answer:

Show the table or make ur question a little more clear so I can help

Step-by-step explanation:

Answer:

0.0668 or 6.68%

Step-by-step explanation:

Variance (V) = 10,000

Standard deviation (σ) = √V= 100

Mean score (μ) = 500

The z-score for any test score X is:

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

For X = 650:

[tex]z=\frac{650-500}{100}\\z=1.5[/tex]

A z-score of 1.5 is equivalent to the 93.32nd percentile of a normal distribution. Therefore, the probability that he or she will make a score of 650 or more is:

[tex]P(X\geq 650)=1-P(X\leq 650)\\P(X\geq 650)=1-0.9332\\P(X\geq 650)=0.0668=6.68\%[/tex]

The probability is 0.0668 or 6.68%

The probability that he or she will make a score of 650 or more is 0.0668.

Let X = Scores made on a certain aptitude test by nursing students

X follows normal distribution with mean = 500 and variance of 10,000.

So, standard deviation = [tex]\sqrt{10000}=100[/tex].

z score of 650 is = [tex]\frac{\left(650-500\right)}{100}=1.5[/tex].

The probability that he or she will make a score of 650 or more is:

[tex]P(X\geq 650)\\=P(z\geq 1.5)\\=1-P(z<1.5)\\=1-0.9332\\=0.0668[/tex]

Learn more: https://brainly.com/question/14109853

Answer:

-4x + 4

Step-by-step explanation:

4x - 2( 4x - 2 )

→ Expand out 2 ( 4x - 2 )

2 ( 4x - 2 ) = 8x - 4

→ Substitute the expanded bracket back into the expression

4x - (8x - 4)

→ Collect the 'x' values

-4x + 4

Answer:

The 99 % confidence interval on the basis of mean is ( 21.7393  ;   22.0257)

Step-by-step explanation:

Mean = Sum of observations / Number of observations

Mean = 21.88 +21.76 +22.14 +21.63+ 21.81 +22.12+ 21.97+ 21.57+ 21.75+ 21.96 +22.20 +21.80/ 12

Mean =x`= 262.59/12=  21.8825

Standard Deviation = s= ∑x²/n - ( ∑x/n)²

∑x²/n= 478.7344 +473.4976 + 490.1796+467.8569+ 475.6761 + 489.2944+ 482.6809+ 465.2649+ 473.0625+ 482.2416 +492.84 + 475.24/ 12

∑x²/n= 5746.5689/12= 478.8807 = 478.881

Standard Deviation = s= ∑x²/n - ( ∑x/n)²

s= 478.881- (21.8825)²= 478.881-478.843= 0.037

The confidence limit 99% for the mean will be determined by

x` ± α(100-1) √s/n

Putting the values in the above equation

= 21.8825 ± 2.58 √0.037/12

Solving the square root

= 21.8825 ± 2.58 (0.05549)

Multiplying the square root with 2.58

=21.8825 ± 0.1432

Adding and subtracting would give

21.7393  ;   22.0257,

Hence the 99 % confidence interval on the basis of mean is ( 21.7393  ;   22.0257)

Answer:

b, c, e

Step-by-step explanation:

the reasons have to include an angle from both of the parallel lines. by using process of elimination it is b, c, e. I also got it right

Answer:

B. a=d

C. c=d

E. b + d=180°

Step-by-step explanation:

Got Correct On MyPath.

Step-by-step explanation:

Formula for compound interest is given by

[tex]A = P(1 + R) ^{n} [/tex]

Where

A is the amount at the end of the period

P is the principal

R is the rate

n is the period

The interest = A - P

From the question

P = $ 3200

n = 3 years

R = 40%

So we have

[tex]A = 3200 \times 2.744[/tex]

A = $ 8780.80

The interest is

$ 8780.80 - $3200

Hope this helps you

Answer:

x=(2+ √-32)/2 or x=(2- √-32)/2

Step-by-step explanation:

x^2 - 2x = -9

x^2 - 2x + 9 =0

x = 2± (√(-2)^2 - 4*1*9)/2*1

Use the quadratic formula in the expression using a=1, b= -2, c=9

x = 2±√4-36 /2

x = 2+√4-36 or x = 2 - √4 - 32 /2

x = (2+√-32) /2 or x=( 2 - √-32 )/2

The solution for the given quadratic equation are (2+i5.7)/2 or (2-i5.7)/2.

The given quadratic equation is x²-2x=-9.

Quadratic formula is the simplest way to find the roots of a quadratic equation.

The roots of a quadratic equation ax² + bx + c = 0 are given by x = [-b ± √(b² - 4ac)]/2a.

By comparing x²-2x+9=0 with ax² + bx + c = 0, we get a=1, b=-2 and c=9

Substitute a=1, b=-2 and c=9 in the quadratic formula, we get

x = [2±√(-2)²-4×1×9)]/2×1

= [2±√4-36]/2

= (2±i5.7)/2

x = (2+i5.7)/2 or (2-i5.7)/2

Therefore, the solution for the given quadratic equation are (2+i5.7)/2 or (2-i5.7)/2.

To learn more about the quadratic formula visit:

https://brainly.com/question/11540485.

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Answer:

1.    [tex]\alpha = 79[/tex] and [tex]\beta = 19[/tex]

2.   [tex]cos(60)[/tex]

3.   [tex]cos(60) = \frac{1}{2}[/tex]

Step-by-step explanation:

Given

[tex]cos(\alpha - \beta )[/tex]

[tex]cos(79)cos(19) + sin(79)sin(19)[/tex]

Solving for [tex]\alpha[/tex] and [tex]\beta[/tex]

In trigonometry;

[tex]cos(\alpha - \beta ) = cos\alpha\ cos\beta + sin\alpha\ sin\beta[/tex]

Equate the above expression to [tex]cos(79)cos(19) + sin(79)sin(19)[/tex]

[tex]cos(\alpha - \beta ) = cos\alpha\ cos\beta + sin\alpha\ sin\beta[/tex] and [tex]cos(\alpha - \beta ) = cos(79)cos(19) + sin(79)sin(19)[/tex]

By comparison

[tex]cos\alpha\ cos\beta + sin\alpha\ sin\beta = cos(79)cos(19) + sin(79)sin(19)[/tex]

Compare expression on the right hand side to the left hand side

[tex]cos\alpha\ cos\beta = cos(79)cos(19) \\\\ sin\alpha\ sin\beta = sin(79)sin(19)[/tex]

This implies that

[tex]cos\alpha\ = cos(79)\\cos\beta = cos(19) \\\\ and\\\\sin\alpha\ = sin(79)\\sin\beta = sin(19)[/tex]

By further comparison

[tex]\alpha = 79[/tex] and [tex]\beta = 19[/tex]

Substitute [tex]\alpha = 79[/tex] and [tex]\beta = 19[/tex] in [tex]cos(\alpha - \beta )[/tex]

[tex]cos(\alpha - \beta ) = cos(79 - 19)[/tex]

[tex]cos(\alpha - \beta ) = cos(60)[/tex]

Hence, the expression is [tex]cos(60)[/tex]

Solving for the exact values;

Express [tex]cos(60)[/tex] as a difference of angles

[tex]cos(60) = cos(90 - 30)[/tex]

Recall that [tex]cos(\alpha - \beta ) = cos\alpha\ cos\beta + sin\alpha\ sin\beta[/tex]

So;

[tex]cos(90- 30 ) = cos(90) cos(30) + sin(90) sin(30)[/tex]

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

In trigonometry;

[tex]cos(90) = 0[/tex]; [tex]cos(30) = \frac{\sqrt{3}}{{2}}[/tex]; [tex]sin(90) = 1[/tex]; [tex]sin(30) = \frac{1}{2}[/tex];

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

[tex]cos(90- 30 ) = cos(90) cos(30) + sin(90) sin(30)[/tex] becomes

[tex]cos(90- 30 ) = 0 * \frac{\sqrt{3}}{2} + 1 * \frac{1}{2}[/tex]

[tex]cos(90- 30 ) = 0 + \frac{1}{2}[/tex]

[tex]cos(90- 30 ) = \frac{1}{2}[/tex]

Hence;

[tex]cos(60) = \frac{1}{2}[/tex]

Answer:

58 hours

Step-by-step explanation:

First week: 25 5/8 hours = 25 hrs 37 mins and 30 sec

Second weeK: 32 5/6 hrs = 32 hrs and 50 mins

To find the toal time in minutes

(37 + 50) mins = 1 hr 27 mins

Threfore, total number of hours he worked in two weeks:

(25 + 32 + 1) hrs = 58 hours

Answer:

The regression model is:

y = 20.29 + 0.73·x

Step-by-step explanation:

In this case a regression model is to be formed to predict the final average in the course based on the first test grade.

Use Excel to form the regression model.

The output is attached below.

The regression model is:

y = 20.29 + 0.73·x

Predict the final average of a students who made an 83 on the first test as follows:

y = 20.29 + 0.73·x

  = 20.29 + 0.73 × 83

  = 80.88

The final average of a students who made an 83 on the first test would be 80.88.

From the output:

R² = 0.839

Then the correlation coefficient will be:

[tex]r=\sqrt{R^{2}}=\sqrt{0.839}=0.91597\approx 0.92[/tex]

The value of r is 0.92.

The coefficient of determination R² specifies the percentage of the variance in the dependent-variable (Y) that is forecasted or explained by linear regression and the forecaster variable (X, also recognized as the independent-variable).

In this case, the R² value of 0.839 implies that 83.9% of the variation in the final average can be explained by the grades in the first test.

Answer:

Hey there!

The line can be expressed into y intercept form, y=3x+1.

Thus, in y=mx+b form, m is the slope, and we see that 3 is the slope of the line.

Let me know if this helps :)

Answer:

Step-by-step explanation:

First, note this parameters from the question.

We let x = number of $5 increases and number of 10 decreases in plates sold.

Our Revenue equation is:

R(x) = (300-10x)(10+5x)

We expand the above equation into a quadratic equation by multiplying each bracket:

R(x) = 3000 + 1500x - 3000x - 1500x^2

R(x) = -1500x^2 - 1500x + 3000 (collect like terms)

Next we simplify, by dividing through by -1500

= 1500x^2/1500 - 1500x/1500 + 3000/1500

= X^2 - x + 2

X^2 - x + 2 = 0

Next, we find the axis of symmetry using the formula x = -b/(2*a) where b = 1, a = 1

X = - (-1)/2*1

X = 1/2

Number of $5 increases = $5x1/2 = $2.5

=$2.5 + $20 = $22.5 ticket price gives max revenue.