Which of these figures has rotational symmetry?

Answer:

Step-by-step explanation:

From the picture attached,

m∠COB = 90° - m∠BOS

              = 90° - 40°

              = 50°

tan(30°) = [tex]\frac{AC}{OC}[/tex]

[tex]\frac{1}{\sqrt{3}}=\frac{AC}{OC}[/tex]

AC = [tex]\frac{OC}{\sqrt{3}}[/tex]  ------(1)

Similarly, tan(50°) = [tex]\frac{BC}{OC}[/tex]

BC = OC[tan(50°)] -------(2)

Now AC + BC = 30 cm

By substituting the values of AC and BC from equation (1) and (2),

[tex]\frac{OC}{\sqrt{3}}+OC(\text{tan}50)=30[/tex]

(1.769)OC = 30

OC = 16.96

1). cos(30°) = [tex]\frac{OC}{AO}[/tex]

[tex]\frac{\sqrt{3}}{2}= \frac{16.96}{OA}[/tex]

[tex]OA=19.58[/tex] cm

Therefore, distance between the ship and town A is 19.58 cm.

2). cos(50°) = [tex]\frac{OC}{OB}[/tex]

0.6428 = [tex]\frac{16.96}{OB}[/tex]

OB = 26.38 cm

Therefore, distance between the ship and town B is 26.38 cm.

Answer:

11 + 10i

Step-by-step explanation:

Just treat i like any other variable, and combine like terms. Hope that helps!

Answer:

yes

Step-by-step explanation:

the answer is c well thats what my teacher said

Answer:

B

Step-by-step explanation:

using sine rule

[tex] \frac{y}{sin \: 45} = \frac{5}{sin \: 45} \\ y = 5[/tex]

using sin rule

[tex] \frac{x}{sin \: 90} = \frac{5}{sin \: 45} \\ \\ 5sin90 = xsin45 \\ \\ x = \frac{5 \: sin \: 90}{sin \: 45} \\ x = \frac{5}{0.7071} \\ x = 7.071[/tex]

x=5√2

Answer:

CI 96 %  =  ( - 0.1128  ; 0.0728 )

CI 95%  =  ( - 0.1087 ; 0.6878 )

The two intervals contain 0 value therefore we can support that there is not statistics difference between the two groups with confidence level of 96 % and  95%

Step-by-step explanation:

Boys sample:

sample size   n₁  = 200

x₁  number of boys saying their parents are very involved in their lives

=  93

p₁ = x₁/n₁   =  93/200  =  0.465  then  q₁ =  1  -  p₁   q₁ = 1 - 0.465  q₁ = 0.535

Girls sample

sample size   n₂  = 300

x₂  number of girls saying their parents are very involved in their lives

=  172

p₂  =  x₂/n₂  =  172/ 300  =  0.573 then  q₂ = 1 -0.573  q₂ =  0.427

CI 96 %      α = 4 %  α = 0.04    α/2 = 0.02  

p₁  -  p₂  =  0.465 -  0.573  = - 0.168

CI 96 %   =  (  p₁  -  p₂ ) ±  z(c) * SE

z(c)  for  α  =  0.02       z(c)  =  - 2.05

SE = √ (p₁*q₁)/n₁  +  (p₂*q₂)/n₂

SE = √ ( 0.465*0.535)/200  +  (0.573*0.427)/300

SE =  √  0.00124  +  0.000815    

SE =  √  0.00205

SE =   0.0453

CI 96 %  =  (  -0.02  ±  ( 2.05 * 0.0453 ) )

CI 96 %  =  (  -0.02  ±  ( 0.0928 ))

CI 96 %  =  ( - 0.1128  ; 0.0728 )

a) CI 95%  α =  5 %   α = 0.05     α/2 =  0.025

SE = 0.0453

z(c) for  0.025 is from z-table   z(c)  =  1.96

CI 95%  =  ( - 0.02 ±  1.96 * 0.0453)

CI 95%  =  ( - 0.02 ± 0.08878 )

CI 95%  =  ( - 0.1087 ; 0.6878 )

Answer:

$3.22 per square feet

Step-by-step explanation:

To solve, I usually set up an equation:

sq ft  = 12 1/2 = 1

 $        40.21     x

Then, use cross multiplication.

(12 1/2)x=40.21

Divide both sides by 12 1/2 or 12.5

x = 3.2168

Round to the hundredths place [because we're dealing with money]

$3.22

I hope this helps!

Answer:

3.22 per sq ft

Step-by-step explanation:

Take the total cost and divide by the amount of tiles

40.21 / 12.5

3.2168 per sq ft

Rounding to the nearest cent

3.22 per sq ft

Answer:

See explanation

Step-by-step explanation:

Given

[tex]M \to[/tex] randomly selecting a male

[tex]B \to[/tex] randomly selecting someone with blue eyes

Solving (a): Interpret P(M|B)

The above implies conditional probability

The interpretation is: the probability of selecting a male provided that a person with blue eyes has been selected

Solving (b): is (a) the same as P(B|M)

No, they are not the same.

The interpretation of P(B|M) is: the probability of selecting a person with blue eyes provided that a male has been selected

Answer:

-1

Step-by-step explanation:

1-2=-1

y=mx+b

b= y intercept

Answer:

-1

Step-by-step explanation:

Hello,

Answer A

[tex]dom (B(n)) =\{0,1,2,3\} =\{ z\ in \ \mathbb{Z} \ |\ 0 \leq z \leq 4\}[/tex]

Answer:

Step-by-step explanation:

X+3 SO = Cymath can't further simplify this.

Please try another operation.

X-220= Cymath can't further simplify this.

Please try another operation.

y= AsymptotesFind the vertical, horizontal and slant asymptotes.

"Asymptotes y=x^2/(x+8)"

"Asymptotes y=1/x"

DifferentiateFind the derivative.

"Differentiate cos(x)^4"

"Differentiate x^5/y for x"

DomainFind the domain of a function.

"Domain y=2/x"

"Domain y=sqrt(x-3)"

Answer:

1st blank=[tex]y_{1}[/tex]

2nd blank=[tex]x_{1}[/tex]

3rd blank= [tex]y_{2}[/tex]

3*27=81

so 1*[tex]y_{1}[/tex]=81

hence [tex]y_{1}[/tex]=81

9* [tex]x_{1}[/tex]= 81

[tex]x_{1}[/tex]=9

27*[tex]y_{2}[/tex]=81

[tex]y_{2}[/tex]=3

Thus solved.

Hope this helps.

Please mark me as brainliest.

Answer:

radius of 80cm is the answer

Answer:

ghthtf

Step-by-step explanation:

tygtgg

Answer:

A seems to be correct

Step-by-step explanation:

Answer:

A=W, B=X, C=Y, D=Z, AB=WX, BC=XY, CD=YZ, AD=WZ

(The second answer down)

Step-by-step explanation:

9514 1404 393

Answer:

  3/4

Step-by-step explanation:

Assuming the faces are numbered 1 to 12, there are 9 faces with values less than 10. Since the outcomes are equally probable and mutually exclusive, the probability of any of the 9 is the sum of their individual probabilities:

  P(n < 10) = 9×1/12 = 9/12 = 3/4

Answer:

The probability that a sample mean is less than 14.99mm=0.066808

Step-by-step explanation:

We are given that

Mean,[tex]\mu=15 mm[/tex]

Standard deviation,[tex]\sigma=0.04 mm[/tex]

n=36

We have to find the probability that a sample mean is less than 14.99mm.

We know that

[tex]P(\bar{x}<a)=P(Z<\frac{\bar{x}-a}{\frac{\sigma}{\sqrt{n}}})[/tex]

Using the formula

[tex]P(\bar{x}<14.99)=P(Z<\frac{14.99-15}{\frac{0.04}{\sqrt{36}}})[/tex]

[tex]P(\bar{x}<14.99)=P(Z<-1.5)[/tex]

=[tex]1-P(Z\geq -1.5)[/tex]

[tex]=1-0.93319[/tex]

=0.066808

Hence,  the probability that a sample mean is less than 14.99mm=0.066808

the third choice

Step-by-step explanation:

check the exchange between logarithms and exponential functions srry but cannot write it here with my phone

Answer:

D) x = e - 1

General Formulas and Concepts:

Pre-Algebra

Algebra II

Step-by-step explanation:

Step 1: Define

Identify

[tex]\displaystyle ln(x + 1) = 1[/tex]

Step 2: Solve for x

Answer:

11.8 yd³

Step-by-step explanation:

Answer:

See Explanation

Step-by-step explanation:

According to the Question,

Thus,

The distance that you get reception is the length of the chord created by the intersection of the circle defining the edge of transmission and the line defining the car trip.

And,

The Transmitter at the origin

City to the north at (0,93)  & City to the east at (78,0)  

the Slope is M=(-93/78)

Intercept is B= y - mx ⇒  93 - (-93/78)(0) = 93

The equation of the line between the cities is y = (-93/78)x + 93

Now, Solve the above two Equations

The intersection is gotten from the picture or solving:

x^2 + [(-93/78)*x + 93]^2 = 69^2

Now,

From the Pythagorean theorem the total distance of the trip is:  

d1 = √(93^2 + 78^2) ≈ 121.37miles  

And the distance when the signal is picked up is:

d2 =√ [(67.952-23.627)^2 + (64.82 - 11.98)^2] ≈ 68.96 miles

You will pick up a signal from the transmitter in (d2/d1)*100 = 56% of the drive.

Answer:

0.007 = 0.7% probability that the proportion of Rolls Royce owners in a sample of 595 Americans would differ from the population proportion by more than 3%

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]

A statistician calculates that 8% of Americans own a Rolls Royce.

This means that [tex]p = 0.08[/tex]

Sample of 595:

This means that [tex]n = 595[/tex]

Mean and standard deviation:

[tex]\mu = p = 0.08[/tex]

[tex]s = \sqrt{\frac{p(1-p)}{n}} = \sqrt{\frac{0.08*0.92}{595}} = 0.0111[/tex]

What is the probability that the proportion of Rolls Royce owners in a sample of 595 Americans would differ from the population proportion by more than 3%?

Proportion above 8% + 3% = 11% or below 8% - 3% = 5%. Since the normal distribution is symmetric, these probabilities are equal, and so we find one of them and multiply by 2.

Probability the proportion is less than 5%:

P-value of Z when X = 0.05. So

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

By the Central Limit Theorem

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

[tex]Z = \frac{0.05 - 0.08}{0.0111}[/tex]

[tex]Z = -2.7[/tex]

[tex]Z = -2.7[/tex] has a p-value of 0.0035

2*0.0035 = 0.0070

0.007 = 0.7% probability that the proportion of Rolls Royce owners in a sample of 595 Americans would differ from the population proportion by more than 3%

Answer:

y=4√3 units

Step-by-step explanation:

Hi there!

We are given ΔABC, which is a right triangle (m<C=90°), m<A=60°, AB=8, and BC=y

We need to find the value of y (BC)

The side AB is the hypotenuse of the  (the side opposite from the right angle).

BC is a leg, which is a side that makes up the right angle.

Now, if we have a right triangle that has one of the acute angles as 60°, the side OPPOSITE from that 60° angle (in this case, BC) is equal to [tex]\frac{a\sqrt{3}}{2}[/tex], where a is the length of the hypotenuse

Since we have the hypotenuse given as 8, the length of BC (y) is [tex]\frac{8\sqrt{3}}{2}[/tex], or 4√3

so y=4√3 units

Hope this helps!

Answer: [tex]\$1.45[/tex]; [tex]\$3.6[/tex]

Step-by-step explanation:

Given

A dozen roses in a gift box costs $21

Similarly, 20 roses in a gift box costs $32.6

Suppose the price of single rose and gift box is [tex]x[/tex] and [tex]y[/tex]

[tex]\therefore 12x+y=21\quad \ldots(i)\\\Rightarrow 20x+y=32.6\quad \ldots(ii)[/tex]

Solving (i) and (ii) ,  we get

[tex]x=\$1.45;y=\$3.6[/tex]

Thus, the price of the one rose is [tex]\$1.45[/tex] and the price of gift box is [tex]\$3.6[/tex]

Answer:

1.45 and 3.5

Step-by-step explanation:

Answer:

1) 114

2) 159

Step-by-step explanation:

2+8+5+9+90 = 114

3+45+111 = 159

Hope this helps.

Answer:

1)144

2)159

..........

Answer:

889 dollars

Step-by-step explanation:

Answer:

en la calasa ni esta en la estacion

Answer:

1. -6x + 14 < -28

6x<42

x<7

2.  3x + 28 < 25

3x < -3

x<-1

Hope This Helps!!!

Answer:

7

Step-by-step explanation:

For simple interest,

I = prt

where I = interest,

p = principal (amount deposited)

r = annual rate of interest

t = time in years

We have r = 2% = 0.02

p = $3,000

I = $420

We need to find t

I = prt

420 = 3000 * 0.02 * t

420 = 60t

t = 420/60

t = 7

Answer: 7 years

Answer:

Exposure to nicotine is the independent variable

Step-by-step explanation:

An independent variable is a factor that remains unchanged (by other factors in the experiment) throughout the course of an experiment. It can however be manipulated by the researcher. A dependent variable, on the other hand, is the factor being measured that relies on the independent variable. In the case above, exposure to 1 hr of nicotine intake forms the independent variable while the levels of hand steadiness, which will be measured, form the dependent variable.