In a certain city district the need for money to buy drugs is stated as the reason for 70% of all thefts. Find the probability that among the next 7 theft cases reported in this district, exactly 3 of them resulted from the need to buy drugs.

Answer:

a) -8/9

b) The series is a convergent series

c) 1/17

Step-by-step explanation:

The series a+ar+ar²+ar³⋯ =∑ar^(n−1) is called a geometric series, and r is called the common ratio.

If −1<r<1, the geometric series is convergent and its sum is expressed as ∑ar^(n−1) = a/1-r

a is the first tern of the series.

a) Rewriting the series ∑(-8)^(n−1)/9^n given in the form ∑ar^(n−1) we have;

∑(-8)^(n−1)/9^n

= ∑(-8)^(n−1)/9•(9)^n-1

= ∑1/9 • (-8/9)^(n−1)

From the series gotten, it can be seen in comparison that a = 1/9 and r = -8/9

The common ratio r = -8/9

b) Remember that for the series to be convergent, -1<r<1 i.e r must be less than 1 and since our common ratio which is -8/9 is less than 1, this implies that the series is convergent.

c) Since the sun of the series tends to infinity, we will use the formula for finding the sum to infinity of a geometric series.

S∞ = a/1-r

Given a = 1/9 and r = -8/9

S∞ = (1/9)/1-(-8/9)

S∞ = (1/9)/1+8/9

S∞ = (1/9)/17/9

S∞ = 1/9×9/17

S∞ = 1/17

The sum of the geometric series is 1/17

Answer:

False

Step-by-step explanation:

AAS is one of the POSTULATE to prove triangles' congruency.

Answer:n

Step-by-step explanation:

Answer:

0.35 cups/hour

Step-by-step explanation:

To be able to determine the rate at which the water is leaking from the pipe with the information given, you have to divide the number of cups by the number of hours in which they were collected:

12 cups/34 hours= 0.35 cups/hour

According to this, the answer is that the rate at which the water is leaking from the pipe is 0.35 cups/hour.

Answer:

Ratio of Able's score to Ben=6:1

Ratio of Ben's score to Cal's=1:2

Ratio of able's score to ben;s score to cal's score=6:1:2

Step-by-step explanation:

Let Ben's score =x

Able scored six times Ben's score

Able=6*x

=6x

Cal scored a third of Able's score

Cal=1/3 of 6x

=1/3(6x)

Ratio of Able's score to Ben

6x:x

=6:1

Ratio of Ben's score to Cal's score

x:1/3(6x)

=x:6x/3

=x:2x

=1:2

Ratio of able's score to ben;s score to cal's score=6:1:2

Answer:

me marca como melhor resposta ☺️❤️

Step-by-step explanation:

.....

Answer:

400

brigadaaaaaaaaaaaaaa

Answer:

a)Randomization condition: Satisfied, as the subjects were randomly selected.

10% condition: Satisfied, as the sample size is less than 10% of the population (U.S. adults).

Sample size condition: Satisfied, as the product between the smaller proportion and the sample size is bigger than 10.

b) The 90% confidence interval for the population proportion is (0.68, 0.70).

Step-by-step explanation:

a) Evaluating the necessary conditions:

Randomization condition: Satisfied, as the subjects were randomly selected.

10% condition: Satisfied, as the sample size is less than 10% of the population (U.S. adults).

Sample size condition: Satisfied, as the product between the smaller proportion and the sample size is bigger than 10.

[tex]n(1-p)=4,726\cdot (1-0.69)=4,726\cdot 0.31=1,465>10[/tex]

b) We have to calculate a 90% confidence interval for the proportion.

The sample proportion is p=0.69.

The standard error of the proportion is:

[tex]\sigma_p=\sqrt{\dfrac{p(1-p)}{n}}=\sqrt{\dfrac{0.69*0.31}{4726}}\\\\\\ \sigma_p=\sqrt{0.000045}=0.007[/tex]

The critical z-value for a 90% confidence interval is z=1.645.

The margin of error (MOE) can be calculated as:

[tex]MOE=z\cdot \sigma_p=1.645 \cdot 0.007=0.01[/tex]

Then, the lower and upper bounds of the confidence interval are:

[tex]LL=p-z \cdot \sigma_p = 0.69-0.01=0.68\\\\UL=p+z \cdot \sigma_p = 0.69+0.011=0.70[/tex]

The 90% confidence interval for the population proportion is (0.68, 0.70).

Answer: The monthly mortgage payment is $640

Step-by-step explanation:

The cost of the house is $159,000

The down payment made is 20%. This means that the amount paid as down payment is

20/100 × 159000 = 31800

The balance to be paid would be

159000 - 31800 = $127200

We would apply the periodic interest rate formula which is expressed as

P = a/[{(1+r)^n]-1}/{r(1+r)^n}]

Where

P represents the monthly payments.

a represents the amount of the loan

r represents the annual rate.

n represents number of monthly payments. Therefore

a = $127200

r = 0.044/12 = 0.0037

n = 12 × 30 = 360

Therefore,

P = 127200/[{(1+0.0037)^360]-1}/{0.0037(1+0.0037)^360}]

P = 127200/[{(1.0037)^360]-1}/{0.0037(1.0037)^360}]

P = 127200/{3.779 -1}/[0.0037(3.779)]

P = 127200/(2.779/0.0139823)

P = 127200/198.75127840198

P = $640

Answer:

The first one matches with f(x)√x because a square root cannot be negative

The second one matches with f(x)=√(x-5) because the square root would be negative if it were less than five.

The third one matches with f(x)=8x because there is nothing that makes it a not possible answer

The last one matches with 7/(x-8) because there cannot be a denominator of zero.

Answer:

Step-by-step explanation:

There are no factors outside the parentheses that need to be distributed, so the parentheses can be simply dropped:

  6 -2x +15 -3x

The terms can be rearranged to put like terms next to each other:

  -2x -3x +6 +15

and the like terms can be combined.

  -5x +21 . . . . simplified expression

__

Put the value of x where x is, then do the arithmetic.

  -5(-0.2) +21 = 1 +21 = 22

In polar coordinates, the inequality changes to

[tex]x^2+y^2\le4x\implies r^2\le4r\cos\theta\implies r\le4\cos\theta[/tex]

which is a circle of radius 2 and centered at (2, 0). The set D is then

[tex]D=\left\{(r,\theta)\mid0\le r\le4\cos\theta\land0\le\theta\le\pi\right\}[/tex]

The integral is then

[tex]\displaystyle\iint_D\frac{y^2}{x^2+y^2}\,\mathrm dx\,\mathrm dy=\int_0^\pi\int_0^{4\cos\theta}\frac{r^2\sin^2\theta}{r^2}r\,\mathrm dr\,\mathrm d\theta[/tex]

[tex]=\displaystyle\int_0^\pi\int_0^{4\cos\theta}r\sin^2\theta\,\mathrm dr\,\mathrm d\theta[/tex]

[tex]=\displaystyle\frac12\int_0^\pi((4\cos\theta)^2-0^2)\sin^2\theta\,\mathrm d\theta[/tex]

[tex]=\displaystyle8\int_0^\pi\cos^2\theta\sin^2\theta\,\mathrm d\theta[/tex]

There are several ways to compute the remaining integral; one would be to invoke the double-angle formula,

[tex]\sin(2\theta)=2\sin\theta\cos\theta[/tex]

so that the integral is

[tex]=\displaystyle8\int_0^\pi\frac{\sin^2(2\theta)}4\,\mathrm d\theta[/tex]

[tex]=\displaystyle2\int_0^\pi\sin^2(2\theta)\,\mathrm d\theta[/tex]

Then invoke another double-angle formula,

[tex]\sin^2\theta=\dfrac{1-\cos(2\theta)}2[/tex]

to change the integral to

[tex]=\displaystyle\int_0^\pi1-\cos(4\theta)\,\mathrm d\theta[/tex]

[tex]=(\pi-\cos(4\pi))-(0-\cos0)=\boxed{\pi}[/tex]

Answer: The answer is (x-5)^2

Answer:

D

Step-by-step explanation:

The volume of pyramid = 1/3 wlh

Where w = width, l = length and h = height

While,

The volume of rectangular prism = wlh

So,

The volume of pyramid = 1/3(the volume of prism)

Answer:

At least 18 of the households have between 2 and 6 televisions.

Step-by-step explanation:

Chebyshev Theorem

The Chebyshev Theorem can also be applied to non-normal distribution. It states that:

At least 75% of the measures are within 2 standard deviations of the mean.

At least 89% of the measures are within 3 standard deviations of the mean.

An in general terms, the percentage of measures within k standard deviations of the mean is given by [tex]100(1 - \frac{1}{k^{2}})[/tex].

In this question:

Mean = 4

Standard deviation = 1

Percentage of households that have between 2 and 6 televisions.

2 = 4 - 2*1

So 2 is two standard deviations below the mean

6 = 4 + 2*1

So 6 is two standard deviations above the mean

By Chebyshev's Theorem, at least 75% of the measures are within 2 standard deviations of the mean.

Out of 24

0.75*24 = 18

At least 18 of the households have between 2 and 6 televisions.

Answer:

x > 1

Step-by-step explanation:

Add 7 to both sides

x > 1

Answer:

numerators:      11  7. 12. 0

                          _  _   _.  _

denominators.  12 512. 10. 78

Step-by-step explanation:

Answer:

11/12 n:11 d:12

7/512 n:7 d:512

12/10 n:12 d:10

0/78 n:0 d:78

Step-by-step explanation:

n=numerator

d=denominator

Answer:

[tex] T_1 = 10*3.5 = 35[/tex]

[tex] T_2 = 20*2.9 = 58[/tex]

[tex] T_3 = 25*3.2 = 80[/tex]

[tex] T_4 = 15*3.4 = 51[/tex]

[tex] \bar X= \frac{T_1 +T_2 +T_3 +T_4}{10+20+25+15}= \frac{35+58+80+51}{10+20+25+15} = 3.2[/tex]

Step-by-step explanation:

For this case we have the following info given:

[tex] n_1= 10 , \bar X_1 = 3.5[/tex] for freshmen

[tex] n_2= 20 , \bar X_2 = 2.9[/tex] for sophomores

[tex] n_3= 25 , \bar X_3 = 3.2[/tex] for juniors

[tex] n_4= 15 , \bar X_4 = 3.4[/tex] for seniors

For this case we can use the formula for the sample mean in order to find the total of each group:

[tex] \bar X =\frac{\sum_{i=1}^n X_i}{n}[/tex]

[tex]T= \sum_{i=1}^n X_i = n *\bar X[/tex]

And replacing we got:

[tex] T_1 = 10*3.5 = 35[/tex]

[tex] T_2 = 20*2.9 = 58[/tex]

[tex] T_3 = 25*3.2 = 80[/tex]

[tex] T_4 = 15*3.4 = 51[/tex]

And the grand mean would be given by:

[tex] \bar X= \frac{T_1 +T_2 +T_3 +T_4}{10+20+25+15}= \frac{35+58+80+51}{10+20+25+15} = 3.2[/tex]

Answer:

y= 2x+1

Step-by-step explanation:

Points:

Form of the line:

Finding the slope:

Line is now:

Using one of the given points to find out the value of b:

So the equation for the line is:

Answer:

72°

Step-by-step explanation:

This is called an isosceles triangle. This means that the 2 angles related to the equal sides, are also equal. Hence, the answer is 72°

Answer:

A

Step-by-step explanation:

Since it is isosceles triangle (two equal sides) therefore, there are 2 equal angles too which at the base (72°)

The total angle of triange is 180°

So 180-72-72=36°

Answer:

As per ASA postulate, the two triangles are congruent.

Step-by-step explanation:

We are given two triangles:

[tex]\triangle ABC[/tex] and [tex]\triangle DEC[/tex].

AD bisects BE.

AB || DE.

Let us have a look at two properties.

1. When two lines are parallel and a line intersects both of them, then alternate angles are equal.

i.e. AB || ED and [tex]\angle B[/tex] and [tex]\angle E[/tex] are alternate angles [tex]\Rightarrow[/tex] [tex]\angle B = \angle E[/tex].

2. When two lines are cutting each other, angles formed at the crossing of two, are known as Vertically opposite angles and they are are equal.

[tex]\Rightarrow \angle ACB = \angle DCE[/tex]

Also, it is given that AD bisects BE.

i.e. EC = CB

1. [tex]\angle B = \angle E[/tex]

2. EC = CB

3. [tex]\angle ACB = \angle DCE[/tex]

So, we can in see that in [tex]\triangle ABC[/tex] and [tex]\triangle DEC[/tex], two angles are equal and side between them is also equal to each other.

Hence, proved that [tex]\triangle ABC[/tex] [tex]\cong[/tex] [tex]\triangle DEC[/tex].

Answer:

Step-by-step explanation:

[tex]y = f(x) =\frac{1}{\sqrt{3 \pi} } e^{-x^{2/3}}[/tex]

y = 0, x = 0 and x = 3

Consider an element of thickness dx at a distance x from the origin. By Cylindirical Shell Method, the volume of the element is given by

[tex]dV=(2\pi rdr)h=(2\pi xdx)f(x) => dV=(2\pi xdx) \frac{1}{\sqrt{3\pi}}e^{-x^{\frac{2}{3}}}[/tex]

[tex]dV=2\sqrt{\frac{\pi}{3}}xe^{-x^{\frac{2}{3}}}dx[/tex]

Integrate the above integral over the limits x=0 to x=3 which implies

[tex]\int_{0}^{V}dV=2\sqrt{\frac{\pi}{3}}\int_{0}^{3}xe^{-x^{\frac{2}{3}}}dx[/tex]

Solve by subsititution

[tex]Let,\\ -x^{\frac{2}{3}}=y => \frac{-2}{3}x^{\frac{-1}{3}}dx=dy => x^{\frac{-1}{3}}dx=\frac{-3}{2}dy[/tex]

Also, apply the new limits

[tex]At,\\\\ x=0, y=0 \ and \ At, x=3, y=-\sqrt[3]{9}[/tex]

This implies,

[tex]\int_{0}^{V}dV=2\sqrt{\frac{\pi}{3}}\int_{0}^{3}x^{\frac{4}{3}}e^{-x^{\frac{2}{3}}}x^{\frac{-1}{3}}dx=2\sqrt{\frac{\pi}{3}}\int_{0}^{-\sqrt[3]{9}}y^{2}e^{y}(\frac{-3}{2})dy[/tex]

[tex]V=-\sqrt{3\pi}\int_{0}^{-\sqrt[3]{9}}y^{2}e^{y}dy[/tex]

Let,

[tex]I=\int_{0}^{-\sqrt[3]{9}}y^{2}e^{y}dy[/tex]

Integrate by parts the above integral

[tex]u=y^2 \ and \ dv=e^ydy => du=2y \ and \ v=e^y[/tex]

Integrate by parts formula

[tex]\int udv=uv-\int vdu => y^2e^y-\int 2ye^ydy[/tex]

Again integrate by parts

[tex]u=y \ and \ dv=e^ydy => du=1 \ and \ v=e^y[/tex]

Integrate by parts formula

[tex]\int udv=uv-\int vdu => y^2e^y-2[ye^y-e^y]=e^y[y^2-2y+2][/tex]

Therefore,

[tex]I=[e^y(y^2-2y+2)]_{0}^{-\sqrt[3]{9}}\\\\=e^{-2.0802}[(2.0802)^2+2(2.0802)+2]-e^{0}[0-0+2]\\\\\frac{(4.3272+4.1604+2)}{8.0061}-2\\\\=\frac{10.4876}{8.0061}-2\\\\=1.3099-2\\\\=-0.6901[/tex]

This implies, the volume is

[tex]V=-\sqrt{3\pi}I\\\\=-\sqrt{3\times 3.142} \times (-0.6901)\\\\=3.0701 \times 0.6901\\\\=2.1186[/tex]

That is, up to three decimal places

[tex]V\approx 2.118[/tex]

Answer:

Step-by-step explanation:

a) 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 = 238

For the alternative hypothesis,

H1: µ < 238

This is a left tailed test

b) Since the population standard deviation is not given, the distribution is a student's t.

Since n = 100

Degrees of freedom, df = n - 1 = 100 - 1 = 99

t = (x - µ)/(s/√n)

Where

x = sample mean = 231

µ = population mean = 238

s = samples standard deviation = 80

t = (231 - 238)/(80/√100) = - 0.88

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

p = 0.19

c) Since alpha, 0.05 < than the p value, 0.19, then we would fail to reject the null hypothesis. Therefore, At a 5% level of significance, the sample data showed insignificant evidence that the mean weekly unemployment insurance benefit in Virginia was below the national average.

d) Since α = 0.05, the critical value is determined from the t distribution table. Recall that this is a left tailed test. Therefore, we would find the critical value corresponding to 1 - α and reject the null hypothesis if the test statistic is less than the negative of the table value.

1 - α = 1 - 0.05 = 0.95

The negative critical value is - 1.66

Since - 0.88 is greater than - 1.66, then we would fail to reject the null hypothesis.

Answer:

1/x = 1/2÷4/5

1/x=1/2 x 5/4

1/x=5/8

5x=8

x=1.6

Answer:

The functions g and f are said to commute with each other if g ∘ f = f ∘ g. Commutativity is a special property, attained only by particular functions, and often in special circumstances. For example, |x| + 3 = |x + 3| only when x ≥ 0. ... The composition of one-to-one functions is always one-to-one.

\

Answer:

14/50 or 7/25

Step-by-step explanation:

cos x = adj/hyp

adj = 14

hyp = 50

---------

you ca learn more about trig

sin x = opp/hyp

tan x = opp/adj

The value of the trigonometric ratio, cos x in a right angle triangle XYZ is   [tex]\dfrac{14}{50}[/tex].

Trigonometric ratios – The relation between the angles and the sides of a right-angle triangle is called Trigonometric ratios.

The six trigonometric ratios are sine (sin), cosine (cos), tangent (tan), cotangent (cot), cosecant (cosec), and secant (sec).

In the given figure a right-angle triangle XYZ we know that

ZY is the length of the perpendicular. XY is the base of the triangle and  ZX is the hypotenuse.

By trigonometric ratio, we know that

[tex]Cos \Theta = \dfrac{adjacent}{hypotenuse}[/tex]

Where [tex]\Theta[/tex] is the acute angle between the base and the Hypotenuse

On substituting value,

[tex]Cos \Theta = \dfrac{14}{50}[/tex]

The value of the trigonometric ratio, cos x in a right angle triangle XYZ   [tex]\dfrac{14}{50}[/tex].

Learn more about Trigonometric ratios here:

https://brainly.com/question/25122825

#SPJ2

Answer:

22. positive

Step-by-step explanation:

–68 + 90

22

Answer:

[tex]-x^5+9x^4-18x^3=0\\-x^3(x^2-9x+18)=0\\-x^3(x-3)(x-6)=0\\\\\\\\x=0\\x=3\\x=6[/tex]

Answer:

63.25 not an integer

Step-by-step explanation:

HCF(a,b)*LCM(a,b)=ab

11*368=64*x

x=11*368/64

x=63.25 not an integer, one of the given numbers must be incorrect

but you may use this method to find it yourself

Answer:

D.

Step-by-step explanation:

Since a quadrilateral inscribed in a circle has its opposite angles adding up to 180°

So,

<MNO + <OLM = 180

82 + <OLM = 180

<OLM = 180-82

<OLM = 98°

Answer:

Due to the fact that there is 21% chance of getting that many girls by chance and also In conjunction to that; there is no test involved as well , we can conclude that the method does not have statistical significance.

The result does not appear to have a practical significance.

Step-by-step explanation:

Given that:

In  a random selection 1936 users, we observed that the method gave birth to  950 boys and 986 girls

There is about a 21​% chance of getting that many girls if the method had no effect.

Due to the fact that there is 21% chance of getting that many girls by chance and also In conjunction to that; there is no test involved as well , we can conclude that the method does not have statistical significance.

Given that:

The number of girls = 986

Number of boys = 950

Number of babies born = 1936

The percentage of girls = number of girls born/ number of babies born

The percentage of girls = 986 /1936

The percentage of girls = 0.5093

The percentage of girls =  50.93%

We can infer that this method does not have a practical significance  because most couples would not prefer to use a method that raise the likelihood of a girl from the approximately 50% rate expected by chance to the 50.93% .

Answer:

169.5 yd²

Step-by-step explanation:

See attachment.

In situations like this, ALWAYS (!) make as sketch.

Divide the areas by adding dotted lines on sensible places, and write in the missing numbers for the correct distances.

The only possible difficult one is the triangle, which is the half of a rectangle. So you are dealing with a series of areas of rectangles. That is really easy if you understand what you are doing.

Total area =

area 1 + area 2 + area 3 + area 4

10*4 + 4*7 + 3*13 + (0.5 * 7*17)

40 + 28 + 42 + 59.5

Total area = 169.5 yd²