Nick,Sarah and Gavyn share some sweets on the ratio 6:2:1. Nick gets 30 more sweets than Gavyn. How many sweets does Sarah get?​

Answer:

[tex]n=(\frac{2.17(0.143)}{0.023})^2 =182.03 \approx 183[/tex]

So the answer for this case would be n=183 rounded up to the nearest integer

Step-by-step explanation:

Information provided

[tex]\bar X[/tex] represent the sample mean

[tex]\mu[/tex] population mean (variable of interest)

[tex]\sigma = 0.143[/tex] represent the population standard deviation

n represent the sample size  

[tex] ME = 0.023[/tex] the margin of error desired

Solution to the problem

The margin of error is given by this formula:

[tex] ME=z_{\alpha/2}\frac{\sigma}{\sqrt{n}}[/tex]    (a)

And on this case we have that ME =0.023 and we are interested in order to find the value of n, if we solve n from equation (a) we got:

[tex]n=(\frac{z_{\alpha/2} \sigma}{ME})^2[/tex]   (b)

The confidence level is 97% or 0.97 and the significance would be [tex]\alpha=1-0.97=0.03[/tex] and [tex]\alpha/2 = 0.015[/tex] then the critical value would be: [tex]z_{\alpha/2}=2.17[/tex], replacing into formula (5) we got:

[tex]n=(\frac{2.17(0.143)}{0.023})^2 =182.03 \approx 183[/tex]

So the answer for this case would be n=183 rounded up to the nearest integer

Answer:

y= 2x +7

Step-by-step explanation:

Slope-intercept form:

y= mx +c, where m is the slope and c is the y-intercept.

Given that the slope is 2, m=2.

y= 2x +c

Given that the y-intercept is -7, c = -7.

y= 2x +7

Answer:

a) Critical value = -1.4052

Since we are checking if the mean time is less than 10 minutes, the rejection area would be

z < -1.4052

b) Option C is correct.

Reject the claim that the mean time is 10 minutes because the test statistic is smaller than the critical point.

That is, the mean time is significantly less than 10 minutes.

Step-by-Step Explanation:

a) Using z-distribution, the critical value is obtained from the confidence level at which the test is going to be performed. Since the hypothesis test tests only in one direction (checking if the claim is less than 10 minutes significantly)

P(z < Critical value) = 0.08

From the z-tables, critical value = -1.4052

Since we are checking if the mean time is less than 10 minutes, the rejection area would be

z < -1.4052

b) We first give the null and alternative hypothesis

The null hypothesis is that there isn't significant evidence to suggest that the mean time is less than 10 minutes.

And the alternative hypothesis is is that there is significant evidence to suggest that the mean time is less than 10 minutes.

To now perform this hypothesis test, we need to obtain the test statistic

Test statistic = (x - μ)/σₓ

x = sample mean = (Σx/N)

The data is

1.2, 2.8, 1.5, 19.3, 2.4, 0.7, 2.2, 0.7, 18.8, 6.1, 6, 1.7, 29.1, 2.6, 0.2, 10.2, 5.1, 0.9, 8.2

Σx = 119.7

N = Sample size = 19

x = sample mean = (119.7/19) = 6.3

μ = standard to be compared against = 10 minutes

σₓ = standard error = (σ/√N)

where N = Sample size = 19

σ = √[Σ(x - xbar)²/N]

x = each variable

xbar = mean = 6.3

N = Sample size = 19

Σ(x - xbar)² = 1122.74

σ = (√1122.74/19) = 7.687

σₓ = (7.687/√19) = 1.7635

Test statistic = (x - μ)/σₓ

Test statistic = (6.3 - 10)/1.7635

= -2.098 = -2.10

z = -2.10 and is in the rejection region, (z < -1.4052), hence, we reject the null hypothesis and the claim and say that the mean time is significantly less than 10 minutes.

The test statistic is less than the critical point, hence, we reject the null hypothesis and the claim and conclude that the mean time is less than 10 minutes.

Hope this Helps!!!

The critical value for the test based on the sampling distribution is -1.4052 and one needs to reject the claim.

From the complete information given, the descriptive statistics from the sample information has been given. The sample mean and variance are given. Therefore, the value of the test statistics from the information is -1.4052.

Also, the conclusion is to reject the claim since the test statistic is smaller than the critical point.

Therefore, the correct option is to reject the claim that the mean time is 10 minutes because the test statistic is smaller than the critical point.

Learn more about sampling on:

https://brainly.com/question/17831271

Answer:

The 98% CI for the mean travel time to the major city is [20.70; 26.14]minutes

Step-by-step explanation:

Hello!

The variable of interest is

X: commute time to a major city.

This variable has a normal distribution

X~N(μ;σ²)

The standard deviation is known to be:

σ= 4.2 minutes

A random sample of n= 13 commute times was taken:

11.5, 13.2, 14.7, 17.1, 18.7, 21.8, 22.4, 25, 26.9, 27.6, 31.1, 35.9, 38.6

You need to estimate the population mean travel time by calculating a 98% CI.

Since the variable has a normal distribution and the population standard deviation is known ,the statistic to use for this interval is the standard normal, then the formula for the interval is:

[X[bar] ± [tex]Z_{1-\alpha /2}[/tex] * [tex]\frac{Sigma}{\sqrt{n} }[/tex]]

The value of the statistic for the 1 - α: 0.98 interval is:

[tex]Z_{1-\alpha /2}= Z_{0.99}= 2.334[/tex]

Next is to calculate the sample mean:

X[bar]= ∑X/n= 304.5/13= 23.42 minutes

[23.42 ± 2.334 * ([tex]\frac{4.2}{\sqrt{13} }[/tex])]

[20.70; 26.14]minutes

With a 98% confidence level you'd expect that the interval [20.70; 26.14]minutes will contain the true mean travel time to the major city.

I hope this helps!

Answer:

[tex]N(T(t)) = 1408t^2 - 385.6t - 105.52[/tex]

Time for bacteria count reaching 8019: t = 2.543 hours

Step-by-step explanation:

To find the composite function N(T(t)), we just need to use the value of T(t) for each T in the function N(T). So we have that:

[tex]N(T(t)) = 22 * (8t + 1.7)^2 - 123 * (8t + 1.7) + 40[/tex]

[tex]N(T(t)) = 22 * (64t^2 + 27.2t + 2.89) - 984t - 209.1 + 40[/tex]

[tex]N(T(t)) = 1408t^2 + 598.4t + 63.58 - 984t - 169.1[/tex]

[tex]N(T(t)) = 1408t^2 - 385.6t - 105.52[/tex]

Now, to find the time when the bacteria count reaches 8019, we just need to use N(T(t)) = 8019 and then find the value of t:

[tex]8019 = 1408t^2 - 385.6t - 105.52[/tex]

[tex]1408t^2 - 385.6t - 8124.52 = 0[/tex]

Solving this quadratic equation, we have that t = 2.543 hours, so that is the time needed to the bacteria count reaching 8019.

Answer:

8

Step-by-step explanation:

2,3,5,11,13,14

Mean= 8

Standard deviation= 4.830

Answer:

C

Step-by-step explanation:

Answer:

[tex]P(1539<X<1580)=P(\frac{1539-\mu}{\sigma}<\frac{X-\mu}{\sigma}<\frac{1580-\mu}{\sigma})=P(\frac{1539-1400}{100}<Z<\frac{1580-1400}{100})=P(1.39<z<1.8)[/tex]

And we can find this probability using the normal standard table with this difference:

[tex]P(1.39<z<1.80)=P(z<1.80)-P(z<1.39)= 0.9641-0.9177=0.0464[/tex]

Step-by-step explanation:

Let X the random variable that represent the weights of a population, and for this case we know the distribution for X is given by:

[tex]X \sim N(1539,1580)[/tex]  

Where [tex]\mu=1400[/tex] and [tex]\sigma=\sqrt{10000}= 100[/tex]

We are interested on this probability

[tex]P(1539<X<1580)[/tex]

And we can solve the problem using the z score formula given by:

[tex]z=\frac{x-\mu}{\sigma}[/tex]

Using this formula we got:

[tex]P(1539<X<1580)=P(\frac{1539-\mu}{\sigma}<\frac{X-\mu}{\sigma}<\frac{1580-\mu}{\sigma})=P(\frac{1539-1400}{100}<Z<\frac{1580-1400}{100})=P(1.39<z<1.8)[/tex]

And we can find this probability using the normal standard table with this difference:

[tex]P(1.39<z<1.80)=P(z<1.80)-P(z<1.39)= 0.9641-0.9177=0.0464[/tex]

Answer:

<XWZ is a right angle

Step-by-step explanation:

Since <YWZ and <XWY both equal 45 degrees, So, <XWZ is a right angle.

Given that ΔYWZ and ΔYXW are similar triangles, the statement that is true about ΔYXW is: B. XWZ is a right angle,

Triangles that are similar possess equal corresponding angles.

We are given that:

ΔYWZ ~ ΔYXW

∠YWZ = ∠XWY = 45 degrees

∠YWZ + ∠XWY = ∠XWZ

45 + 45 = ∠XWZ

∠XWZ = 90 degrees (right angle).

Therefore, given that ΔYWZ and ΔYXW are similar triangles, the statement that is true about ΔYXW is: B. XWZ is a right angle,

Learn more about similar triangles on:

https://brainly.com/question/2644832

Answer:

the answer is the first option

Answer:

6%

Step-by-step explanation:

We have to calculate the interest rate in the note, we must follow the following steps, calculate the amount of time remaining from the year 2021, as follows:

interest is for 5 months i.e. from Aug 01 to Dec 31 for year 2021 , so it means it would be 5/12 months.

We have to calculate the interest as follows:

I = P * R * T

We replace:

200 = 8000 * R * 5/12

we solve for R

200 * 12/5 = 8000 * R

R * 8000 = 480

R = 480/8000

R = 0.06

Which means that the interest rate on the note is 6%

Answer:

[tex] P(X<12000)[/tex]

And for this case we can use the cumulative distribution function given by:

[tex] P(X\leq x) =\frac{x-a}{b-a}, a \leq x \leq b[/tex]

And using this formula we have this:

[tex] P(X<12000)= \frac{12000-10100}{14700-10100}= 0.41[/tex]

Then we can conclude that the probability that your bid will be accepted would be 0.41

Step-by-step explanation:

Let X the random variable of interest "the bid offered" and we know that the distribution for this random variable is given by:

[tex] X \sim Unif( a= 10100, b =14700)[/tex]

If your offer is accepted is because your bid is higher than the others. And we want to find the following probability:

[tex] P(X<12000)[/tex]

And for this case we can use the cumulative distribution function given by:

[tex] P(X\leq x) =\frac{x-a}{b-a}, a \leq x \leq b[/tex]

And using this formula we have this:

[tex] P(X<12000)= \frac{12000-10100}{14700-10100}= 0.41[/tex]

Then we can conclude that the probability that your bid will be accepted would be 0.41

Answer:

Step-by-step explanation:

You take 70.3m^3 multiple with 880kg /m^3 divide with 5300.kg will give you the answer cause I tried it and it worked 100% true.

I hope tis helps .

Answer:

The x-coordinate is the solution to x - 4 = 0, which is x = 4 and the y-coordinate is 3 so the answer is (4, 3).

Answer:

-50

Step-by-step explanation:

10-10(5)

Or regular

10-10 = 0

-10 = -10

4 times

-10(4) = 40

-->

-10 - 40 = -50

-50

Answer:

-50

Step-by-step explanation:

Answer:

Step-by-step explanation:

The equation of this circle is (x - 3)^2 + (y - 3)^2 = 12^2.

Let's substitute the coordinates of the given point and compare the results to the above equation:  do they produce a correct statement?

(-6 - 3)^2 + (-5 - 3)^2 = ?

9^2 + 8^2 = 145

Because r = 12, the above result would need to be 144, not 145, if the given point were actually on the circle.  We must conclude that (-6, -5) lies just outside the circle.

81 + 64 = 144  

Answer:

  A.  The weekly usage of both coupons is decreasing and approaching a horizontal asymptote as x gets larger.

Step-by-step explanation:

You can see that f(x) is a decreasing exponential function because the base is 0.75, a value less than 1. The horizontal asymptote is 10, the constant added to the exponential term.

Obviously, g(x) is decreasing. If we assume it is an exponential function, we know there is a horizontal asymptote. (Every exponential function has a horizontal asymptote.)

__

If you use your graphing calculator's exponential regression function, you can find a good model for g(x) is ...

  g(x) = 950·0.7^x +12

That is, it is an exponential function that decays faster than f(x), but has a higher horizontal asymptote.

_____

Both functions are decreasing and approaching horizontal asymptotes.

Answer:

x = 150°

Step-by-step explanation:

Start by cutting the shape into two triangles by bisecting the 30°

Now we have two triangles that have two angles 90° and 15°

Subtract 15° from 90°, you'll get 75°

Double 75° because x is split into 2

150° = x

Also, were given 3 angles, this is a quadrilateral.

90° + 90° +  30° = 210°

360° - 210° = 150°

Answer:

150°

Step-by-step explanation:

OA⊥AC and OB⊥BC

∠A+∠B+∠C+∠O=360°

90°×2+30°+x=360°

x=360°-210°=150°

Answer:216

Step-by-step explanation:The formula to find the area of a triangle is Length times Base divided by 2. The length of the triangle could be 18 or 24, but that doesn’t matter. The base could also be 18 or 24, but that also doesn’t matter, because the hypotenuse (the longest part of a right triangle, in this case being 30), is not a part of the formula. 18 times 24 is 432, and 432 divided by 2 is 216. So the area is 216

Answer:

Mean: 94.5.

Median: 99.5

Standard deviation: 33.1

We can tell the owner that the applicants don't have a score significantly below from 100.

Step-by-step explanation:

First, we analize the sample and calculate the statistics (mean, median and standard deviation).

Mean of the sample:

[tex]M=\dfrac{1}{n}\sum_{i=1}^n\,x_i\\\\\\M=\dfrac{1}{10}(95+105+120+81+90+115+99+100+130+10)\\\\\\M=\dfrac{945}{10}\\\\\\M=94.5\\\\\\[/tex]

The median, as the sample size is an even number, can be calculated as the average between the fifth and sixth value, sort by value:

[tex]\text{Median}=\dfrac{99+100}{2}=99.5[/tex]

The standard deviation is:

[tex]s=\sqrt{\dfrac{1}{n-1}\sum_{i=1}^n\,(x_i-M)^2}\\\\\\s=\sqrt{\dfrac{1}{9}((95-94.5)^2+(105-94.5)^2+(120-94.5)^2+. . . +(10-94.5)^2)}\\\\\\s=\sqrt{\dfrac{9834.5}{9}}\\\\\\s=\sqrt{1092.7}=33.1\\\\\\[/tex]

To tell if this sample has a value significantly lower than the expected score of 100, we should make a hypothesis test.

The claim is that the mean score is significantly lower than 100.

Then, the null and alternative hypothesis are:

[tex]H_0: \mu=100\\\\H_a:\mu< 100[/tex]

The significance level is 0.05.

The sample has a size n=10.

The sample mean is M=94.5.

As the standard deviation of the population is not known, we estimate it with the sample standard deviation, that has a value of s=33.1.

The estimated standard error of the mean is computed using the formula:

[tex]s_M=\dfrac{s}{\sqrt{n}}=\dfrac{33.1}{\sqrt{10}}=10.467[/tex]

Then, we can calculate the t-statistic as:

[tex]t=\dfrac{M-\mu}{s/\sqrt{n}}=\dfrac{94.5-100}{10.467}=\dfrac{-5.5}{10.467}=-0.53[/tex]

The degrees of freedom for this sample size are:

[tex]df=n-1=10-1=9[/tex]

This test is a left-tailed test, with 9 degrees of freedom and t=-0.53, so the P-value for this test is calculated as (using a t-table):

[tex]\text{P-value}=P(t<-0.53)=0.306[/tex]

As the P-value (0.306) is bigger than the significance level (0.05), the effect is not significant.

The null hypothesis failed to be rejected.

There is not enough evidence to support the claim that the mean score is significantly lower than 100.

Answer:

2 and -5

Step-by-step explanation:

[tex]5+\dfrac{10}{x}=x+8 \\\\\\-3+\dfrac{10}{x}=x \\\\\\-3x+10=x^2 \\\\\\x^2+3x-10=0 \\\\\\(x+5)(x-2)=0 \\\\\\x=2,-5[/tex]

Hope this helps!

Answer:

Step-by-step explanation:

the equation of a line is given as

[tex]y= mx+c[/tex]

where

m= is the slope

c= is the y intercept

their mistake is that they did not recall that if the "c" is not shown, it is assumed to be zero (0)

Answer:

(h, k) is the point that represents the vertex of this absolute value function

Step-by-step explanation:

Recall that the vertex of an absolute value function occurs when the expression within the absolute value symbol becomes "zero", because it is at this point that the results in sign differ for x-values to the left and x-values to the right of this boundary point.

Therefore, in your case, the vertex occurs at  x = h, and when x = h, then you can find the y-value of the vertex by looking at what f(h) renders:

f(h) = a | h - h | + k = 0 + k = k

Then the point of the vertex is: (h, k)

Answer:

D on edg2020

Step-by-step explanation:

Took the test

Answer:

Three: x = 400

Four : 9

Step-by-step explanation:

Three

a = 10*√2

2a = √(2x)                    Square both sides.

4a^2 = 2x                     Divide both sides by 2

2a^2 = x                       Put a = 10√2 into a^2

2(10√2)^2 = x               Square a

2(100*2) = x                 Multiply the result by 2.

2(200) = x

x = 400

Four

x^(a^2) / x ^(b^2) = x^36

Substitute a + b = 4 in for b.

x^(a^2) / x^(4 - a)^2 = x^36

Subtract powers

x^(a^2 - (4 - a)^2 = x^36

x^(a^2 - (16 - 8a + a^2) = x^36

Gather like terms

x^(8a - 16) = x^36

The powers are now equal

8a - 16 = 36      

Add 16 to both sides

8a = 36 + 16

8a = 52

Divide by 8

a = 6.5

Solve for b

a + b = 4

6.5 + b = 4

b = 4 - 6.5

b = - 2.5

a - b = 6.5 - (- 2.5) = 9

Answer:

The answer is false

Step-by-step explanation:

For two polygons to be similar, both of the following must be true: Corresponding angles are congruent. Corresponding sides are proportional.

Answer:

1.2kg

Step-by-step explanation:

6 identical toys weigh 1.8kg.

1 toy would weigh:

1.8/6 = 0.3

0.3 kg.

Multiply 0.3 with 4 to find how much 4 identical toys would weigh.

0.3 × 4 = 1.2

4 identical toys would weigh 1.2kg

Answer:

[tex]1.2kg[/tex]

Step-by-step explanation:

6 identical toys weigh = 1.8kg

Let's find the weight of 1 toy ,

[tex]1.8 \div 6 = 0.3[/tex]

Now, lets find the weigh of 6 toys,

[tex]0.3 \times 4 = 1.2kg[/tex]

Answer:

a. The interval that contains 95% of the sample means is 16.3 and 19.7 hours. Because the sample mean is between these two values, we have support for the results of the CEO study by the Harvard Business School.

Step-by-step explanation:

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

Normal probability distribution

When the distribution is normal, we use the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore 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 pvalue, we get the probability that the value of the measure is greater than X.

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.

In this question, we have that:

[tex]\mu = 18, \sigma = 5.2, n = 35, s = \frac{5.2}{\sqrt{35}} = 0.879[/tex]

95% of the sample means:

From the: 50 - (95/2) = 2.5th percentile.

To the: 50 + (95/2) = 97.5th percentile.

2.5th percentile:

X when Z has a pvalue of 0.025. So X when Z = -1.96.

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

By the Central Limit Theorem

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

[tex]-1.96 = \frac{X - 18}{0.879}[/tex]

[tex]X - 18 = -1.96*0.879[/tex]

[tex]X = 16.3[/tex]

97.5th percentile:

X when Z has a pvalue of 0.975. So X when Z = 1.96.

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

[tex]1.96 = \frac{X - 18}{0.879}[/tex]

[tex]X - 18 = 1.96*0.879[/tex]

[tex]X = 19.7[/tex]

95% of the sample means are between 16.3 and 19.7 hours. This interval contains the sample mean of 16.8 hours, which supports the study.

So the correct answer is:

a. The interval that contains 95% of the sample means is 16.3 and 19.7 hours. Because the sample mean is between these two values, we have support for the results of the CEO study by the Harvard Business School.

Answer:

The value of 7.9-4.36 is 3.54

The value of 5.27 + 3.5 is 8.77

Step-by-step explanation:

Answer:

You're pretty sure that your candidate for class president has about 55% of the votes in the entire school. but you're worried that only 100 students will show up to vote. how often will the underdog (the one with 45% support) win? to find out, you set up a simulation.

a. describe-how-you-will-simulate a component.

b. describe-how-you-will-simulate a trial.

c. describe-the-response-variable

Step-by-step explanation:

Part A:

A component is one voter's voting. An outcome is a vote in favor of our candidate.

Since there are 100 voters, we can stimulate the component by using two random digits from 00 - 99, where the digits 00 - 64 represents a vote for our candidate and the digits 65 - 99 represents a vote for the under dog.

Part B:

A trial is 100 votes. We can stimulate the trial by randomly picking 100 two-digits numbers from 00 - 99.

And counted how many people voted for each candidate.  Whoever gets the majority of the votes wins the trial.

Part C:

The response variable is whether the underdog  wins or not.

To calculate the experimental probability, divide the number of trials in which the simulated underdog wins by the total number of trials.

Answer:

7.005 m^2.

Step-by-step explanation:

We can split this into one vertical rectangle   3.45 * 0.9 m^2

2 rectangles 2 * 0.75  = 1.5 m^2

1 rectangle 1.2 * 0.75 m^2

=  3.105 + 2 * 1.5 + 0.9

= 7.005 m^2.