Mathematics I need help

Answer:

They all test relationship when it involves two variables

Explanation:

All of the statistical methods listed above all measure the relationship between two variables.

The Chi Square test tests the relationship between two nominal/categorical variable groups.

The Pearson correlation test tests relationship between two continuous variables using the Pearson correlation coefficient to determine statistical relationship between them.

The simple linear regression measures relationship between two variables: dependent/response variable and independent/explanatory variable, to see if a relationship exists between by way of influence of the independent variable on the dependent variable.

Answer: adults = 79

children = 158

student = 46

Step-by-step explanation:

Let a = adults

Let c = children

Let s = student

From the information given,

a + c + s = 283 ....... i

c/a = 2, c = 2a ....... ii

5c + 7s + 12a = 2060 ...... iii

Put the value of c = 2a into equation i

a + c + s = 283

a + 2a + s = 283

3a + s = 283

s = 283 - 3a

Note that c = 2a

From equation iii

5c + 7s + 12a = 2060

5(2a) + 7(283 - 3a) + 12a = 2060

10a + 1981 - 21a + 12a = 2060

10a + 12a - 21a = 2060 - 1981

a = 79

Note c = 2a

c = 2 × 79 = 158

Since a + c + s = 283

79 + 158 + s = 283

s = 283 - 237

s = 46

adults = 79

children = 158

student = 46

Answer:

Hope this helps!

Answer:

B. the mean

Step-by-step explanation:

According to the Bar Chart shown, the number of DVDs sold at a local music store during one week are displayed.

Therefore, the measure(s) of central tendency that can be used to determine the average number of DVDs sold each day is the mean.

This is because the mean is the sum total of the number of DVDs sold, divided by the number, which gives the average.

Answer:

The Mean

Step-by-step explanation:

I took the test

Answer:

See attachment for graph

The height of the arch is: 120 m

The width to the nearest meter, at the base of the arch is 22 m

Step-by-step explanation:

Given

[tex]h = -0.06d^2 + 120[/tex]

Solving (a): The graph

See attachment for graph

Variable h is plotted on the vertical axis while variable d is plotted on the horizontal axis.

Solving (b): The height

The curve of [tex]h = -0.06d^2 + 120[/tex] opens downward. So, the maximum point on the vertical axis represents the height of the arch,

Hence:

[tex]height = 120[/tex]

Solving (c): The width

The curve touches the horizontal axis at two different points.

[tex]x_1 = -11[/tex]

[tex]x_2 = 11[/tex]

The absolute difference of both points represents the width.

So:

[tex]Width = |x_2 - x_1|[/tex]

[tex]Width = |11 - -11|[/tex]

[tex]Width = |11 +11|[/tex]

[tex]Width = |22|[/tex]

Hence:

[tex]Width = 22[/tex]

Answer:

7.5 ft³/min

Step-by-step explanation:

Let x be the depth below the surface of the water. The height, h of the water is thus h = 10 - x.

Now, the volume of water V = Ah where A = area of isosceles base of trough = 1/2bh' where b = base of triangle = 4 ft and h' = height of triangle = 1 ft. So, A = 1/2 × 4 ft × 1 ft = 2 ft²

So, V = Ah = 2h = 2(10 - x)

The rate of change of volume is thus

dV/dt = d[2(10 - x)]/dt = -2dx/dt

Since dV/dt = 15 ft³/min,

dx/dt = -(dV/dt)/2 = -15 ft³/min ÷ 2 = -7.5 ft³/min

Since the height of the water is h = 10 - x, the rate at which the water level is rising is dh/dt = d[10 - x]/dt

= -dx/dt

= -(-7.5 ft³/min)

= 7.5 ft³/min

And the height at this point when x = 8 inches = 8 in × 1 ft/12 in  = 0.67 ft is h = (10 - 0.67) ft = 9.33 ft

Answer:

Step-by-step explanation:

a.) it's just mean, variance

so here it's just 12,6.25

b.) For the x bar thing just divide the variance by the number of people (mean stay the same)

the variance is then (2.5²/34)= .1838

which makes it (12,.1838)

c.) here we don't use x bar (and so it's normal (12,2.5²))

p(11.6) = (11.6-12)/(2.5)= -.16 = .4364

p(12.4)= (12.4-12)/2.5 = .16= .5636

.5636-.4364= .1272

d.) here we use x bar because it's asking for an average so it's normal (12, .1838)

same deal

p(11.6)=(11.6-12)/√.1838= -.93295= .1762

p(12.4)= (12.4-12)/√.1838= .93295= .8238

.8238-.1762= .6476

d.) no because they're probably IID

f.) It's average so here we use x bar

q1 is just the 25th percentile

the 25th percentile is -.6745

-.6745=(x-12)/(√.1838)= 11.711

q3 is the 75th percentile

.6745=(x-12)/√.1838

x=12.289

The interquartile range is just the difference between the two

12.289-11.711= .5784

Answer:

Place value of 1 = 1 × 10 = 10

Step-by-step explanation:

In 382619,

Place of 1 = Tens

Place value of 1 = 1 × 10 = 10

Answer:

[tex]{ \tt{2x + 4y = 8 - - - (a)}} \\ { \tt{x = 3y - 6 - - - (b)}} [/tex]

Substitute for x in equation (a) :

[tex]{ \tt{2(3y - 6) + 4y = 8}} \\ { \tt{6y - 12 + 4y = 8}} \\ { \tt{10y = 20}} \\ y = 2[/tex]

Substitute for y in equation (b) :

[tex]{ \tt{x = (3 \times 2) - 6}} \\ x = 0[/tex]

2x+4y =8

x=3y-6 ——> x–3y=–6

x–3y = – 6 ] ×(–2) ——> –2x +6y=12

2x+4y=8

–2x+6y =12

__o_o____

0+10y=20 —> 10y= 20 —> y= 20/10 —> y= 2

2x+4y=8 —> 2x + 4(2) = 8 —> 2x + 8=8 —> 2x = 0 —> x=0

(x,y) —> (0,2)

Answer:

[tex]\{a[/tex] ∈ [tex]R\ -21 \le a \le \infty \}[/tex] --- set builder

[tex][-21,\infty)[/tex] --- interval notation

Step-by-step explanation:

Given

[tex]-3a - 15 \le -2a + 6[/tex]

Required

Solve

Collect like terms

[tex]-3a + 2a \le 15 + 6[/tex]

[tex]-a \le 21[/tex]

Divide by -1

[tex]a \ge - 21[/tex]

Rewrite as:

[tex]-21 \le a[/tex]

Using set builder

[tex]\{a[/tex] ∈ [tex]R\ -21 \le a \le \infty \}[/tex]

Using interval notation, we have:

[tex][-21,\infty)[/tex]

Answer:

12x^3 is equivalent to

12x*12x*12x which if we multiply is

1728x

we divide by 4x

1728x divided by 4x=432x

Hope This Helps!!!

Answer:

3x^2

Step-by-step explanation:

when u divide 12x^3/4x....u divide 12/4=3 along with the x also..tat is x^3/x=x^2

Answer:

36281629273781646181993836619946527189119292937467482919198$7473828191927364732818919283838292927383883829118661552621718919191019284746617171819001187373765252728

Step-by-step explanation:

173899918377+28910873638282

Answer:

40 years old.

Step-by-step explanation:

We can let Elga's age equal [tex]x[/tex]. Alvin's age can be equal to [tex]y[/tex]. We can make several equations from the information we know. We know that Elga's age plus five equal's Alvin's age.

[tex]x+5=y[/tex]

We also know that the sum of their ages is 85.

[tex]x+y=85[/tex]

We can substitute [tex]x+5[/tex] for [tex]y[/tex] in the second equation since [tex]x+5=y[/tex], so we have the following equation:

[tex]x+(x+5)=85[/tex]

We can combine like terms to get

[tex]2x+5=85[/tex]

Subtracting 5 from both sides results in

[tex]2x=80[/tex]

After that, we can divide both sides by 2 to get

[tex]x=40[/tex]

Thus, Elga is 40 years old.

Answer:

e = 40

a=45

Step-by-step explanation:

a + e = 85

a = e+5

e + 5 + e = 85

2e = 80

e = 40

a=45

The angle C of the triangle ABC is ( π - 3a ).

The angle is defined as the span between two intersecting lines or surfaces at or close to the point where they meet.

The angle will be calculated as follows:-

We know that the sum of the angles of the triangle is 180 degrees or π in radians.

∠A + ∠B + ∠C = π

a + 2a + ∠C = π

∠C = π - a - 2a

∠C = π - 3a

Therefore angle C of the triangle ABC is ( π - 3a ).

To know more about an angle follow

https://brainly.com/question/25770607

#SPJ2

Answer:

(0.3049 ; 0.3751)

Step-by-step explanation:

The confidence interval for proportion can be obtained using the relation :

Phat ± Zcritical * [√phat(1-phat) / n]

phat = x / n

Sample size, n = 700

x = 238

phat = 238/700 = 0.34

Zcritical at 95% = 1.96

C.I = 0.34 ± 1.96 * [√0.34(1-0.34) / 700]

C.I = 0.34 ± 1.96 * 0.0179045

C. I = 0.34 ± 0.0350928

Lower boundary = 0.34 - 0.0350928 = 0.3049

Upper boundary = 0.34 + 0.0350928 = 0.37509

(0.3049 ; 0.3751)

Answer:

y = (-1/3)x + 2

Step-by-step explanation:

Since points (3,1) and (-6,4) lie on y = (-1/3)x + c , it should satisfy the this equation. Thus, intercept is 2.

Answer:

m = -⅓

Step-by-step explanation:

m = (y2- y1)/(x2 - x1)

m = (4 -1)/(-6-3)

m = -⅓

Answer:

55.75 cents per ounce

Step-by-step explanation:

Take the cost and divide by the number of ounces

We want cents per ounce so change dollars to cents

446 / 8

55.75 cents per ounce

Answer:

A. 8x = amount of broccoli needed

B. 4 people; 32÷8=4

Step-by-step explanation:

A. the variable (x) represents the amount of people.

B. 32 ounces divided by 8 ounces is enough for four people.

Answer:

The choose (A)

y=(x-1)²-2

Answer:

The empirical rule, the approximate percentage of trees planted between 38 and 68 is 99.7%.

Step-by-step explanation:

The Empirical Rule states that, for a normally distributed random variable:

Approximately 68% of the measures are within 1 standard deviation of the mean.

Approximately 95% of the measures are within 2 standard deviations of the mean.

Approximately 99.7% of the measures are within 3 standard deviations of the mean.

In this problem, we have that:

Mean of 62, standard deviation of 8.

What is the approximate percentage of trees planted between 38 and 86?

38 = 62 - 3*8

86 = 62 + 3*8

So within 3 standard deviations of the mean, which, by the empirical rule, the approximate percentage of trees planted between 38 and 68 is 99.7%.

The answer is 36 degrees

Step 1

Angle GEH=180-2x (angles on a a straight line are supplementary)

Step 2

4x= G^+GE^H(sum of exterior angle)

4x=x+(180-2x)

4x=180-x

4x+x=180

5x=180

x=36 degrees

Answer:

i put in 3 to make 23436 because 36 is divisible by 6

Answer:

The total distance Allie traveled was 0.81 miles.

Step-by-step explanation:

Since Allie rode her bike up a hill at an average speed of 12 feet / second, and she then rode back down the hill at an average speed of 60 feet / second, and the entire trip took her 2 minutes, to determine what is the total distance she traveled, the following calculation must be performed:

12 + 60 = 72

72 x 60 = 4320

1000 feet = 0.189394 miles

4320 feet = 0.8181818 miles

Therefore, the total distance Allie traveled was 0.81 miles.

9514 1404 393

Answer:

  (11, 3)

Step-by-step explanation:

That point is ...

  P = a + (1/6)(b -a) = (5a +b)/6

  P = (5(14, -1) +(-4, 23))/6 = (70-4, -5+23)/6 = (11, 3)

The point of interest is (11, 3).

Answer:

The coordinates of the point that is 1/6 of the way from a to b is thus (11, 3)

Step-by-step explanation:

Let's look first at the x coordinates of the two given points:  14 and -4.  From 14 to -4 is a decrease of 18.  Similarly, from y = -1 to y = 23 is an increase of 24.

Starting at a(14, -1) and adding 1/6 of the change in x, which is -18, we get the new x-coordinate 14 + (1/6)(-18), or 14 - 3, or 11.  Similarly, adding 1/6 of the increase in y of 24 yields -1 + 4, or 3.

The coordinates of the point that is 1/6 of the way from a to b is thus (11, 3)

Answer:

0.9606 = 96.06% probability that the proportion of politicians who are lawyers will differ from the total politicians proportion by less than 4%

Step-by-step explanation:

To solve this question, we need to understand the normal probability distribution and the central limit theorem.

Normal Probability Distribution

Problems of normal distributions can be solved using the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:

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

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

Central Limit Theorem

The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].

For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.

For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean [tex]\mu = p[/tex] and standard deviation [tex]s = \sqrt{\frac{p(1-p)}{n}}[/tex]

Suppose 46% of politicians are lawyers.

This means that [tex]p = 0.46[/tex]

Sample of size 662

This means that [tex]n = 662[/tex]

Mean and standard deviation:

[tex]\mu = p = 0.46[/tex]

[tex]s = \sqrt{\frac{p(1-p)}{n}} = \sqrt{\frac{0.46*0.54}{662}} = 0.0194[/tex]

What is the probability that the proportion of politicians who are lawyers will differ from the total politicians proportion by less than 4%?

p-value of Z when X = 0.46 + 0.04 = 0.5 subtracted by the p-value of Z when X = 0.46 - 0.04 = 0.42. So

X = 0.5

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

By the Central Limit Theorem

[tex]Z = \frac{X - \mu}{s}[/tex]

[tex]Z = \frac{0.5 - 0.46}{0.0194}[/tex]

[tex]Z = 2.06[/tex]

[tex]Z = 2.06[/tex] has a p-value of 0.9803

X = 0.42

[tex]Z = \frac{X - \mu}{s}[/tex]

[tex]Z = \frac{0.42 - 0.46}{0.0194}[/tex]

[tex]Z = -2.06[/tex]

[tex]Z = -2.06[/tex] has a p-value of 0.0197

0.9803 - 0.0197 = 0.9606

0.9606 = 96.06% probability that the proportion of politicians who are lawyers will differ from the total politicians proportion by less than 4%

Answer:

Use suitable identity to find the product (3-2x)(3+2x).Find the remainder when x³+ 3x²+3x+1 is divided by x+1.On a plane surface we can find straight lines.8√15 + 2√3The decimal form of 36 100(a-b)³ = a ³- ........ 3 + 3ab²-b³In the Cartesian plane the horizontal line is called .........The coefficient of x² in 2-x²+ x³ is -1.√225 is an irrational number.The coordinates of a point on x-axis is (y, 0).The coordinates of a point on x-axis is (y, 0).The coordinates of a point on x-axis is (y, 0).The coordinates of a point on x-axis is (y, 0).

Answer:

answer

x = -13/ 15, 0

Step-by-step explanation:

15x^2 + 13 x = 0

or, x(15x + 13) = 0

either, x = 0

or, 15x + 13 = 0

x = -13/15

Answer:

The answer should be C...............

imma sorry if I'm wrong