Six measurements were made of the magnesium ion concentration (in parts per million, or ppm) in a city's municipal water supply, with the following results. It is reasonable to assume that the population is approximately normal. Based on a 95% confidence interval for the mean magnesium ion concentration, is it reasonable to believe that the mean magnesium ion concentration may be greater than 199.5? (Hint: you should first calculate the 95% confidence interval for the mean magnesium ion concentration.)
a) The likelihood cannot be determined
b) Yes
c) No

Answer:

C. 1/25

Step-by-step explanation:

5^-2=5^(2*-1)

5^2=25

25^-1=1/25

Answer:

It is C 1/25 because it won't be -25 because a negative times a negative is a positive

Step-by-step explanation:

Answer:

x=7, y=2

Step-by-step explanation:

Solve2x+3y=20for x:

2x+3y=20

2x+3y+−3y=20+−3y

2x=−3y+20

2x/2=-3y+20/2

x= -3/2 y

Answer:

1x1x6x5x4x3x2x1 = 720 also they can sit in:

6x1x1x5x4x3x2x1 = 720

6x5x1x1x4x3x2x1 = 720

6x5x4x1x1x3x2x1 = 720

6x5x4x3x1x1x2x1 = 720

6x5x4x3x2x1x1x1 = 720

6x5x4x3x2x1x1x1 = 720 or you could have gone 720 x 7

Answer:

A. 32.25

Step-by-step explanation:

Because of the first row, we know that to find the cost, we are multipling the gallons by 2.15.

so [tex]15*2.15=32.25[/tex]

So the answer is A.

Hope this helps!

Plx give brainliest

Answer:

h = 16.23 m

The cannonball will hit the wall at 16.23m from the ground.

Step-by-step explanation:

Given;

Initial speed v = 62m/s

Angle ∅ = 25°

Horizontal distance d = 260 m

Height of wall y = 20

Resolving the initial speed to vertical and horizontal components;

Horizontal vx = vcos∅ = 62cos25°

Vertical vy = vsin∅ = 62cos25°

The time taken for the cannon ball to reach the wall is;

Time t = horizontal distance/horizontal speed

t = d/vx (since horizontal speed is constant)

t = 260/(62cos25°)

t = 4.627 seconds.

Applying the equation of motion;

The height of the cannonball at time t is;

h = (vy)t - 0.5gt^2

Acceleration due to gravity g = 9.81 m/s

Substituting the given values;

h = 62sin25×4.627 - 0.5×9.81×4.627^2

h = 16.2264134736

h = 16.23 m

The cannonball will hit the wall at 16.23m from the ground.

Answer:

Step-by-step explanation:

[tex]\int\limits^{\infty}_0 {A^2_1} (e^{-r/a})r^2dr= {A^2_1}\int\limits^{\infty}_0r^2(e^{-r/a})^2\, dr)[/tex]

[tex]=A_1^2\int\limits^{\infty}_0 r^2e^{-2r/a}\ dr[/tex]

[tex]=A_1^2[\frac{r^2e^{2r/a}}{-2/a} |_0^{\infty}-\int\limits^{\infty}_0 2r\frac{e^{-2r/a}}{-2/a} \ dr][/tex]

[tex]=A^2_1[0+\int\limits^{\infty}_0 a\ r\ e^{-2r/a}\ dr][/tex]

[tex]=A^2_1[\frac{a \ r \ e^{-2r/a}}{-2/a} |^{\infty}_0-\int\limits^{\infty}_0 \frac{a \ e^{-2r/a}}{-2/a} \ dr][/tex]

[tex]=A_0^2[0-0+\int\limits^{\infty}_0 \frac{a^2}{2} e^{-2r/a}\ dr\\\\=A_1^2\frac{a^2}{2} \int\limits^{\infty}_0 e^{-2r/a}\ dr\\\\=A_1^2\frac{a^2}{2} [\frac{e^{-2r/a}}{-2/a} ]^{\infty}_0[/tex]

[tex]=\frac{A_1^2a^2}{2} -\frac{a}{2} [ \lim_{r \to \infty} [e^{-2r/a} -e^0]\\\\=\frac{A_1^2a^2}{2} -(\frac{a}{2}) (0-1)[/tex]

[tex]=\frac{A_1^2a^3}{4}[/tex]

[tex]\therefore A_1^2\int\limits^{\infty}_0 r^2(e^{-r/a}) \ dr =\frac{A_1^2a^3}{4}[/tex]

Find the unique positive value of A1

[tex]=4\pi (\frac{A_1^2a^3}{4} )\\\\=A_1^2a^3\pi\\\\A_1^2=\frac{1}{a^3\pi} \\\\A_1=\sqrt{\frac{1}{a^3\pi} }[/tex]

Answer:

The answer is "[tex]58.625 cm^3[/tex]"

Step-by-step explanation:

Consider the cube volume of x =6 cm.

Substitute x = 6 cm in the volume

[tex]V= x^3\\\\ V = (6)^3\\\\ V = 216[/tex]

Therefore, whenever the cube volume

[tex]x=6 \ cm \ is \ V= 216 \ cm^3[/tex]

Then consider the cube's volume

x = 6.5 cm.

Substitute x = 6.5 cm in the volume

[tex]V_1 = x^3\\V_1 = (6.5)^3\\V_1 = 274.625 \\[/tex]   by using the calculator.

Therefore, when another cube volume

[tex]x = 6.5 cm \\\\ V_1 = 274.625 cm^3.[/tex]

The real volume error x = 6.5 cm instead of x = 6 cm is calculated as,

[tex]dV= V_1-V\\[/tex]

     [tex]=274.625-216\\=58.625\\[/tex]

Hence, the actual error in the volume when x = 6.5 cm instead of x = 6 cm is [tex]58.625 \ cm^3.[/tex]

Answer:

There are 60 marbles in the bag

Step-by-step explanation:

The total number of marbles  times the probability of red marbles = number of red marbles

total * 7/10 = 42

Multiply each side by 10/7

total * 7/10 * 10/7 = 42*10/7

total

60

There are 60 marbles in the bag

Answer:

A) -x + y = 2

B) x + 2y = 4

we add both equations

3 y = 6

y = 2

We put y = 2 into equation B)

x + 2 * 2 = 4

x = 0

***********************************************

A) -2x + y = 6

B) x + y = 0

We multiply B) by 2

B) 2 x + 2 y = 0 then we add A)

A) -2x + y = 6

3y = 6

y = 2

Therefore x = -2

Step-by-step explanation:

Answer:

7x -14 = jl

Step-by-step explanation:

Assuming a straight line

jm+ ml = jl

5x-8 + 2x-6 = jl

Combine like terms

7x -14 = jl

Answer:

The answer is C because DC = BA and DA = CB (given) and AC = CA (reflexive property).

Answer:

At a significance level of 0.05, there is enough evidence to claim that there is a significant relationship between x and y.

P-value = 0.003.

Step-by-step explanation:

If we perform a regression analysis relating x and y, we get the best fitting line with equation:

[tex]y=15.82x+92.9[/tex]

and a correlation coefficient r:

[tex]r=0.693[/tex]

We have to test the hypothesis, where the alternative hypothesis claims that there is a relationship between these two variables, and the null hypothesis claiming there is no relationship (meaning that the correlation is not significantly different from 0).

This can be written as:

[tex]H_0: \rho=0\\\\H_a:\rho\neq0[/tex]

where ρ is the population correlation coefficient for x and y.

The significance level is assumed to be 0.05.

The sample size is n=16.

The degrees of freedom are df=14.

[tex]df=n-2=16-2=14[/tex]

The test statistic can be calculated as:

[tex]t=\dfrac{r\sqrt{n-2}}{\sqrt{1-r^2}}=\dfrac{0.693\sqrt{14}}{\sqrt{1-(0.693)^2}}=\dfrac{2.593}{0.721}=3.597[/tex]

For a test statistic t=2.05 and 14 degrees of freedom, the P-value is calculated as:

[tex]\text{P-value}=2\cdot P(t>3.597)=0.003[/tex]

The P-value (0.003) is smaller than the significance level (0.05), so the effect is significant enough.

The null hypothesis is rejected.

At a significance level of 0.05, there is enough evidence to claim that there is a significant relationship between x and y.

Answer:

  4

Step-by-step explanation:

Let's try this a different way than perhaps the usual way. Let r represent the reciprocal of the number.

  r(1/r -1) -1/2r = 5/8

  1 -r -1/2r = 5/8 . . . . . . eliminate parentheses

  -3/2r = -3/8 . . . . . . . . collect terms, subtract 1

  (-3/2)/(-3/8) = 1/r = 4 . . . . . divide by (-3/8)r because we actually want 1/r

The number is 4.

_____

Check

The reciprocal of the number is 1/4.

1 less than the original number is 4 -1 = 3. The product of these is 3/4.

__

Half the reciprocal of the original number is (1/2)(1/4) = 1/8.

Then the difference between these is ...

  3/4 -1/8 = (6 -1)/8 = 5/8 . . . . as required.

Answer:

300/60=5 more words per minute

80+5 = 85 words per minute

or

80 x 60 = 4800 + 300 = 5100

5100 / 60 = 85 words per minute

Hope this helps

Step-by-step explanation:

[tex]answer \\ 13.5 \: m/s \\ given \\ initial \: velocity(u) = \: 3 \: m/s \\ acceleration(a) = 1.5 \: m/s ^2\\ time(t) = 7 \: second \\ now \\ v = u + at \\ or \: v = 3 + 1.5 \times 7 \\ \: or \: v = 3 + 10.5 \\ v = 13.5 \: m/s \\ hope \: it \: helps[/tex]

Answer: 3 hours and 18 minutes.

Step-by-step explanation:

Answer:

The required probability is 0.4828.

Step-by-step explanation:

We are given that a company is producing two types of ski goggles. Thirty percent of the production is of type A, and the rest is of type B.

Five percent of all type A goggles are returned within 10 days after the sale, whereas only two percent of type B are returned.

Let the probability that production is of Type A = P(A) = 30%

Probability that production is of Type B = P(B) = 1 - P(A) = 1 - 0.30 = 70%

Also, let R = event that pair of goggles are returned

So, the probability that type A goggles are returned within 10 days after the sale = P(R/A) = 5%

Probability that type B goggles are returned within 10 days after the sale = P(R/B) = 2%  

Now, given a pair of goggles is returned within the first 10 days after the sale, the probability that the goggles returned are of type B is given by = P(B/R)

We will use the concept of Bayes' Theorem to calculate the above probability.

So,  P(B/R)  =  [tex]\frac{P(B) \times P(R/B)}{P(A) \times P(R/A)+P(B) \times P(R/B)}[/tex]

                   =  [tex]\frac{0.70 \times 0.02}{0.30 \times 0.05+0.70 \times 0.02}[/tex]

                   =  [tex]\frac{0.014}{0.029}[/tex]  =  0.4828

Answer:

The expected value of the random variable with the given probability distribution = 12 .52

Step-by-step explanation:

Given data

 x    :   0         1            5       10     1000

p(x)  :  0.33  0.32   0.24     0.10    0.01

The expected value of the given random variable of given probability distribution

E(X)  =  ∑ x p ( X = x)

E(X)  =  0 × 0.33 + 1 × 0.32 + 5 × 0.24 + 10× 0.10 + 1000×0.01

E (X)  =  12.52

Answer:an=20(-1/2)^n-1

Step-by-step explanation:

Answer:

  it is the complement of 28°

Step-by-step explanation:

Angle DAB made by a tangent and a chord to the point of tangency is equivalent to every other inscribed angle that intercepts the same arc. Those angles have half the measure of the central angle ACB intercepting the same arc.

In isosceles triangle ABC the base angles (shown as 28°) are the complement of half the measure of the central angle. Hence angle DAB will be the complement of the angle marked 28°.

  angle DAB = 90° -28° = 62°

Answer:

No, the events are not mutually exclusive because they share the common outcomes of the student working and playing volleyball on certain days.

Step-by-step explanation:

A and B are mutually exclusive events if they cannot occur at the same time. This means that A and B do not share any outcomes and P(A AND B)=0.

In this case, A and B have outcomes in common since the student both works and plays volleyball on Tuesdays and Thursdays. Thus, the events are not mutually exclusive.  

Answer:

4 pounds of lime and 5 pounds of pears

Step-by-step explanation:

I + P = 9

0.5l + 1.5P = 9.5

I = 9 - P

0.5(9 - P) + 1.5P = 9.5

4.5-0.5P + 1.5P = 9.5

4.5 + P (1P) = 9.5

P = 9.5-4.5 = 5

I = 9 - 5 = 4

Answer: 4 pounds of lime and 5 pounds of pears

Answer:

Step-by-step explanation:

We would set up the hypothesis test. This is a test of a single population mean since we are dealing with mean

For the null hypothesis,

H0: μ = 904

For the alternative hypothesis,

Ha: μ < 904

This is a left tailed test

Since the number of samples is small and no population standard deviation is given, the distribution is a student's t.

Since n = 10,

Degrees of freedom, df = n - 1 = 10 - 1 = 9

t = (x - µ)/(s/√n)

Where

x = sample mean = 805

µ = population mean = 904

s = samples standard deviation = 158

t = (805 - 904)/(158/√10) = - 1.98

We would determine the p value using the t test calculator. It becomes

p = 0.039

Since alpha, 0.05 > than the p value, 0.03953, then we would reject the null hypothesis. Therefore, the correct option is:

2. P-value 0.039, there is sufficient evidence to conclude the mean lifetime of its SuperGlo light bulbs is less than 904 hours.

Answer:

52% probability that a randomly selected puppy in the shelter will get adopted and live 7 or more years

Step-by-step explanation:

We use the conditional probability formula to solve this question. It is

[tex]P(B|A) = \frac{P(A \cap B)}{P(A)}[/tex]

In which

P(B|A) is the probability of event B happening, given that A happened.

[tex]P(A \cap B)[/tex] is the probability of both A and B happening.

P(A) is the probability of A happening.

In this question:

Event A: A puppy is adopted.

Event B: The puppy lives 7 or more years.

An animal shelter has a 65% adoption rate for puppies

This means that [tex]P(A) = 0.65[/tex]

Of the puppies who are adopted, 80% live to be 7 years or older.

This means that [tex]P(B|A) = 0.8[/tex]

What is the probability that a randomly selected puppy in the shelter will get adopted and live 7 or more years

[tex]P(B|A) = \frac{P(A \cap B)}{P(A)}[/tex]

[tex]P(A \cap B) = P(A)*P(B|A)[/tex]

[tex]P(A \cap B) = 0.65*0.8[/tex]

[tex]P(A \cap B) = 0.52[/tex]

52% probability that a randomly selected puppy in the shelter will get adopted and live 7 or more years

Answer:

The 95% confidence interval for the mean of all body temperatures is between 97.76 ºF and 99.12 ºF

Step-by-step explanation:

We have the standard deviation for the sample, so we use the t-distribution to solve this question.

The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So

df = 10 - 1 = 9

95% confidence interval

Now, we have to find a value of T, which is found looking at the t table, with 9 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.95}{2} = 0.975[/tex]. So we have T = 2.2622

The margin of error is:

M = T*s = 2.2622*0.3 = 0.68

In which s is the standard deviation of the sample.

The lower end of the interval is the sample mean subtracted by M. So it is 98.44 - 0.68 = 97.76 ºF

The upper end of the interval is the sample mean added to M. So it is 98.44 + 0.68 = 99.12 ºF

The 95% confidence interval for the mean of all body temperatures is between 97.76 ºF and 99.12 ºF

Answer:

Geometric Sequence.

Step-by-step explanation:

Geometric sequence. If you take a close look at the graph, it never touches the x - axis. If you use division in a geometric sequence, you will get a very small number, but you will never touch the axis.

Answer:

The way adolescents spend their time can strongly influence their health later in life. For youth to maintain a healthy future, they need plenty of sleep; good nutrition; regular exercise; and time to form relationships with family, friends, and caring adults. Additionally, the time adolescents spend in school and in after-school activities with peers and adults can advance healthy academic, emotional, social, and physical development. The amount of time they spend on screens and in social media may also influence adolescents’ overall well-being.

The American Time Use Survey, collected by the U.S. Bureau of Labor Statistics, contains detailed information about how individuals ages 15 and older use their time and provides a picture of a typical weekday and weekend day for a high school teen during the school year. Here we specifically analyze how adolescents ages 15-19 who are enrolled in high school spend their time.

Step-by-step explanation:

The PIN is 4829

Step-by-step explanation:

let s take 4 numbers a b c and d

the PIN is abcd

we know that

(1) a = b/2

(2) b+c=10

(3) d=b+1

(4) a+b+c+d=23

from (2) c = 10 - b

from (3) d = b + 1

so (4) gives

b/2 + b + 10 - b + b +1 = 23

so

3/2 b = 23 -11 = 12

b = 12*2/3 = 8

so d = 9

c = 10-8=2

and a = 4

so the PIN is 4829

thank you

Answer:

200 feet

Step-by-step explanation:

Area of the warehouse [tex]=60,000$ ft^2[/tex]

Let the length of the warehouse=l

The warehouse's width is exactly  [tex]\dfrac23[/tex] of its length

Therefore: Width of the warehouse[tex]=\dfrac23l[/tex]

Area =Length X Width

Therefore:

[tex]\dfrac23l*l=60000\\$Cross multiply\\2l^2=60000*3\\2l^2=180000\\$Divide both sides by 2\\2l^2 \div 2=180000 \div 2\\l^2=90000\\l^2=300^2\\$Length, l=300 feet\\Recall: Width =\dfrac23l\\$Therefore, Width of the warehouse=\dfrac23*300=200$ feet[/tex]

Answer:

C.

Step-by-step explanation:

According to theorem, congruent angles has congruent sides opposite to them so,

RS = TU

Now

12x+4 = 11x+15

12x-11x = 15-4

So

x = 11

Now

TU = 11x+15

= 11(11)+15

= 121+15

= 136 units