1/2x - 7 = 1/3 (x-12)

aleksklad [387]

Answer:8/10

Step-by-step explanation:

7 0

3 years ago

The delivery times for all food orders at a fast-food restaurant during the lunch hour are normally distributed with a mean of m

UkoKoshka [18]

Answer:

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

$X \sim N(14.7,3.7)$

Where $\mu=14.7$ and $\sigma=3.7$

Since the distribution of X is normal then we know that the distribution for the sample mean $\bar X$ is given by:

$\bar X \sim N(\mu, \frac{\sigma}{\sqrt{n}})$

And we have;

$\mu_{\bar X}= 14.70$

$\sigma_{\bar X} =\frac{3.7}{\sqrt{40}}= 0.59$

Step-by-step explanation:

Assuming this question: The delivery times for all food orders at a fast-food restaurant during the lunch hour are normally distributed with a mean of 14.7 minutes and a standard deviation of 3.7 minutes. Let R be the mean delivery time for a random sample of 40 orders at this restaurant. Calculate the mean and standard deviation of $\bar X$ Round your answers to two decimal places.

Previous concepts

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".

Solution to the problem

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

$X \sim N(14.7,3.7)$

Where $\mu=14.7$ and $\sigma=3.7$

Since the distribution of X is normal then we know that the distribution for the sample mean $\bar X$ is given by:

$\bar X \sim N(\mu, \frac{\sigma}{\sqrt{n}})$

And we have;

$\mu_{\bar X}= 14.70$

$\sigma_{\bar X} =\frac{3.7}{\sqrt{40}}= 0.59$

4 0

3 years ago

Please help solve for angles Q X and Z

Iteru [2.4K]

Answer:

125

Step-by-step explanation:

Sum of Exterior Angles must add to 360 so

$60 + 70 + 40 + 65 + x = 360$

$235 + x = 360$

$x = 125$

6 0

3 years ago

getting home from trick or treat celia and emma counted their candies. half of celias candies is equal to 2/3 of emmas candies.

blagie [28]

Candies with celias and emmas is 60 and 45 respectively.

<u>Solution:</u>

Given, Getting home from trick or treat celia and emma counted their candies. Half of celias candies is equal to 2/3 of emmas candies.

They had a total of 105 candies altogether.

We have to find how many candies did each of them have.

Let the number of candies with celias be n, then number of candies with emma will be 105 – n.

Now according to given condition.

$\begin{array}{l}{\frac{1}{2} \times \text { celias candies count }=\frac{2}{3} \times \text { emmas candies count }} \\\\ {\rightarrow \frac{1}{2} \times n=\frac{2}{3} \times(105-n)} \\\\ {\rightarrow 3 \times n=2 \times 2 \times(105-n)} \\\\ {\rightarrow 3 \times n=2 \times 2 \times(105-n)} \\\\ {\rightarrow 3 n=4(105-n)} \\\\ {\quad \rightarrow 3 n=420-4 n} \\\\ {\rightarrow 3 n=420-4 n} \\\\ {\rightarrow 3 n+4 n=420} \\\\ {\rightarrow 7 n=7 \times 60} \\\\ {\rightarrow n=60}\end{array}$

Hence, candies with celias and emmas is 60 and 45 respectively.

4 0

3 years ago

HELP PLEASE!!! Thanks!

Irina18 [472]

Answer:

2) $\frac{\sqrt{77}}{11}$

3) 5√2

Step-by-step explanation:

Simplest radical form of an expression is the expression in radical so that there are no more square roots, cube roots, 4th roots, etc left to find, after rationalising the denominator ( if needed ).

2. Here the given expressions,

$\frac{\sqrt{7}}{\sqrt{11}}$