i am really confused ​

Answer:

0.104 = 10.4% probability that at least 2 drive without a seatbelt.

Step-by-step explanation:

For each person, there are only two possible outcomes. Either they drive without a seatbelt, or they do not. The probability of a person driving without a seatbelt is independent of any other person. This means that we use the binomial probability distribution to solve this question.

Binomial probability distribution

The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]

In which [tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by the following formula.

[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]

And p is the probability of X happening.

20% of the people in Fiji drive the car without seatbelt.

This means that [tex]p = 0.2[/tex]

3 people are randomly selected

This means that [tex]n = 3[/tex]

Find the probability that at least 2 drive without a seatbelt?

This is:

[tex]P(X \geq 2) = P(X = 2) + P(X = 3)[/tex]

In which

[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]

[tex]P(X = 2) = C_{3,2}.(0.2)^{2}.(0.8)^{1} = 0.096[/tex]

[tex]P(X = 3) = C_{3,3}.(0.2)^{3}.(0.8)^{0} = 0.008[/tex]

[tex]P(X \geq 2) = P(X = 2) + P(X = 3) = 0.096 + 0.008 = 0.104[/tex]

0.104 = 10.4% probability that at least 2 drive without a seatbelt.

Answer:

The point estimate for the true difference between the population means is of -2.62 years.

The 95% confidence interval for the difference between the true mean ages for cars owned by students and faculty is between -3.4 years and -1.84 years.

Step-by-step explanation:

Before building the confidence interval, we need to understand the central limit theorem, and subtraction between normal variables.

Central Limit Theorem

The Central Limit Theorem estabilishes 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]

Subtraction of normal variables:

When we subtract normal variables, the mean is the subtraction of the mean, while the standard deviation is the square root of the sum of variances.

A sample of 138 cars owned by students had an average age of 5.13 years. The population standard deviation for cars owned by students is 3.45 years.

This means that:

[tex]\mu_{s} = 5.13, \sigma_{s} = 3.45, n = 138, s_s = \frac{3.45}{\sqrt{138}} = 0.2937[/tex]

A sample of 111 cars owned by faculty had an average age of 7.75 years.  The population standard deviation for cars owned by faculty is 2.08 years.

This means that [tex]\mu_{f} = 7.75, \sigma_{f} = 2.08, n = 111, s_f = \frac{2.08}{\sqrt{111}} = 0.2658[/tex]

Difference between the true mean ages for cars owned by students and faculty.

s - f

Mean:

[tex]\mu = \mu_s - \mu_f = 5.13 - 7.75 = -2.62[/tex]

This is the point estimate for the true difference between the population means.

Standard deviation:

[tex]s = \sqrt{s_s^2+s_f^2} = \sqrt{0.2937^2+0.2658^2} = 0.3961[/tex]

Confidence interval:

We have that to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval divided by 2. So:

[tex]\alpha = \frac{1 - 0.95}{2} = 0.025[/tex]

Now, we have to find z in the Ztable as such z has a pvalue of [tex]1 - \alpha[/tex].

That is z with a pvalue of [tex]1 - 0.025 = 0.975[/tex], so Z = 1.96.

Now, find the margin of error M as such

[tex]M = zs = 1.96*0.3961 = 0.78[/tex]

The lower end of the interval is the sample mean subtracted by M. So it is -2.62 - 0.78 = -3.4

The upper end of the interval is the sample mean added to M. So it is -2.62 + 0.78 = -1.84

The 95% confidence interval for the difference between the true mean ages for cars owned by students and faculty is between -3.4 years and -1.84 years.

Answer:

x ≈ 3.29

Step-by-step explanation:

Take the logarithm of both sides of the equation to remove the variable from the exponent.

Exact Form:

x  = [tex]\frac{ln(200)}{ln(5)}[/tex]

Decimal Form:

x  =  3.29202967 … ≈ 3.29 (Round to what the question asks, in this case, I rounded to 2 decimal places)

Answer:

ln200/ln5

Step-by-step explanation:

ln5^x=ln200

xln5=ln200

x=ln200/ln5

Answer:

angle b= 86 degrees

Step-by-step explanation:

hope this helps, have a nice day :)

Answer:

ok

Step-by-step explanation:

whats the question?

9514 1404 393

Answer:

  (d)

Step-by-step explanation:

The purpose of the mnemonic SOH CAH TOA is to help you remember that ...

   Tan = Opposite/Adjacent

Answer:

49 is the area for the circle

Answer:

ANSWER : 4

Step-by-step explanation:

hello :

tanA=7/2    means : A= tan^-1 (7/2) =74°

Answer: NO GRAPH DUMMY

Step-by-step explanation:

Answer:

B)  x = 12

Step-by-step explanation:

m∡EOU = m∡TQE

m∡EOU =180 - (39+45) = 96°

m∡TQE:  7x + 12 = 96

7x = 84

x = 12

Answer:

8/30015 or .037%

Step-by-step explanation:

16/30 × 15/29 × 14/28 × 13/27 × 12/26 x 11/25 x 10/24 × 9/23 × 8/22 × 7/21

= 8/30015

Answer:

I believe it's the 4th one the 2nd on the right under that the one i think is selected looks right!

Answer is 4th one.

Step-by-step explanation:

Hope i helped! Your welcome! Have a great week!

Answer:

Seattle is more likely to have rain.

Step-by-step explanation:

Seattle has a 75% chance of rain

Tacoma has a 1/4 chance of rain.

100% = 4/4

75% = 3/4

50% = 2/4

25% = 1/4

25% < 75%

Answer:

Step-by-step explanation:

Answer: x=8

Step-by-step explanation:

We know that it is a square, so the diagonals divide the four triangles evenly.

A whole circle will have 360°. When it is divides into 4, each angle will be

360/4=90°

The vertex of each triangle will be 90°

And the given vertex equation is 8x+26

8x+26=90

8x+26-26=90-26

8x=64

x=8

Hope this helps!! :)

Please let me know if you have any questions

Answer:

216

Step-by-step explanation:

^

Answer:

647.668 cm³

Step-by-step explanation:

12.5 kg = 12500 g

12500 g/19.3 g/cm³ = 647.668 cm³

Answer:

1/20 of 2 minutes = 6 seconds

Answer:

1/20; 0.05; 5%

Step-by-step explanation:

Well, 2 minutes is 120 seconds, 6/120 simplified is 1/20, and decimal form would be 0.05, which is 5%

Answer:

50 square meters should be your answer

Step-by-step explanation:

The formula of the Surface Area of a sphere is 4πr2 (4*r*squared)

if the radius of the sphere is 2 m, our formula will become 4π(2)[squared]

let us break this down into two pieces:

4π = 12.5663706144

2[squared] = 4

Then when we multiply our answers:

12.5663706144 * 4 = 50.2654824576

since it says to round it to the nearest whole number, we can round this to 50

I HOPE YOU HAVE A WONDERFUL DAY AND GET THIS CORRECT!!!

Please rate and heart if my answer helped you!!!!

Answer:

B

Step-by-step explanation:

brainliest?

Answer:

2/5+1/5=3/5

Step-by-step explanation:

What I think ur trting to say; Noah is thinking of two fractions that have the same sum of 3/5. Each fraction has a numerator of 1. What are the denimonitors of the fractions? Enter your answers in the box

answer

2 and 10

Answer:

15.70

Step-by-step explanation:

Answer:

78.5

Step-by-step explanation:

Formula: a = πr², r = d/2

Given: π = 3.14, d = 10

Sub: a = (3.14)r²

Find r.

r = 10/2

r = 5

Sub: a = (3.14)5²

Simplify: a = (3.14)25

Solve: a = 78.5

The answer is 78.5.

If this truly helped you, help me out by thanking me.

-Xax.

Answer:

x=1/6 or 0.16

Step-by-step explanation:

x has to be whatever makes the equation true.

does 1/3 +2= 4 alone no does it = 4 when you do the 1/3(1/6) yes

Answer:

A

Step-by-step explanation:

All of the rest you have to pay off. A savings account is a good place to keep money safe for the future, and you can also make interest.

Answer:

I have come to the conclusion that it is A. 112,000

Answer:

d) 127,000 members

Step-by-step explanation:

In this problem we have an exponential function of the form

where  a is the initial value

b is the base

The base is equal to  b=1+r

r is the average rate

In this problem we have  a=23,000 members

r=5%=5/100=0.05

b=1+0.05=1.05

substitute

x ----> is the number of years since 1985

How many members will there be in 2020?

x=2020-1985=35 years

substitute in the function

Round to the nearest thousand

Answer:

1780.43

Step-by-step explanation:

Given:

P = 800

r = 10% or 0.1

t = 8

Work:

[tex]A=Pe^{rt}\\\\A=800e^{0.1*8}\\\\A=800e^{0.8}\\\\A=1780.43[/tex]

Answer:

The car gets 35 miles per gallons.

Step-by-step explanation:

Answer:

A

Step-by-step explanation:

We want to solve the equation:

[tex]5\sin(2x)=3\cos(x)[/tex]

To do so, we can rewrite the equation.

Recall the double-angle identity for sine:

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

By substitution:

[tex]5\left(2\sin(x)\cos(x)\right)=3\cos(x)[/tex]

Distribute:

[tex]10\sin(x)\cos(x)=3\cos(x)[/tex]

We can subtract 3cos(x) from both sides:

[tex]10\sin(x)\cos(x)-3\cos(x)=0[/tex]

And factor:

[tex]\cos(x)\left(10\sin(x)-3\right)=0[/tex]

Hence, our answer is A.

*It is important to note that we should not divide both sides by cos(x) to acquire 10sin(x) = 3. This is because we need to find the values of x, and one or more may result in cos(x) = 0 and we cannot divide by 0. Hence, we should subtract and then factor.

Answer:

A. cosx(10sinx-3)=0

Step-by-step explanation:

5(2sinxcosx)=3cosx

10sinxcosx-3cosx=0

cosx(10sinx-3)=0

Answer:

3.24

Step-by-step explanation:

9 takes up 3.24 of 36%

Answer:

9 is 36% of 25

Step-by-step explanation:

36%×x=9

36/100×x=9

x=9×100/36

x=25

Answer:

409 i would say

Step-by-step explanation:

very sorry is its wrong!!! :(

Answer:

prob d im guessing :^)

Step-by-step explanation:

tell me if i got it right or wrong i will fix if needed