9x-12y=12 in slope intercept form

The lifespan (in days) of the common housefly is best modeled using a normal curve having mean 22 days and standard deviation 5.

Natasha_Volkova [10]

Answer:

Yes, it would be unusual.

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 normally distributed samples are solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

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.

If $Z \leq -2$ or $Z \geq 2$ , the outcome X is considered unusual.

Central Limit Theorem

The Central Limit Theorem estabilishes that, for a normally distributed random variable X, with mean $\mu$ and standard deviation $\sigma$ , the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean $\mu$ and standard deviation $s = \frac{\sigma}{\sqrt{n}}$ .

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:

$\mu = 22, \sigma = 5, n = 25, s = \frac{5}{\sqrt{25}} = 1$

Would it be unusual for this sample mean to be less than 19 days?

We have to find Z when X = 19. So

$Z = \frac{X - \mu}{\sigma}$

By the Central Limit Theorem

$Z = \frac{19 - 22}{1}$

$Z = -3$

$Z = -3 \leq -2$ , so yes, the sample mean being less than 19 days would be considered an unusual outcome.

7 0

3 years ago

A recipe uses 3 cups of flour and 2 cups of sugar write the ratio as a fraction

Verdich [7]

3:2 is ratio
3/2 cups of flour per cup of sugar

5 0

3 years ago

Read 2 more answers

Classify each pair of angels listed below as adjacent or vertical.

Stolb23 [73]

Answer:

ntersecting lines DA and CE.

To find:

Each pair of adjacent angles and vertical angles.

Solution:

Adjacent angles are in the same straight line.

Pair of adjacent angles:

(1) ∠EBD and ∠DBC

(2) ∠DBC and ∠CBA

(3) ∠CBA and ∠ABE

(4) ∠ABE and ∠EBD

Vertical angles are opposite angles in the same vertex.

Pair of vertical angles:

(1) ∠EBD and ∠CBA

(2) ∠DBC and ∠EBA

5 0

3 years ago

Select the correct answer.

Fudgin [204]

A) an answer that cannot be written as a fraction.

6 0

3 years ago

A top-loading washing machine has a cylindrical basket that rotates about a vertical axis. The basket of one such machine starts

damaskus [11]

Answer:

$n_{tot}=44rev$

Step-by-step explanation:

In order to solve this problem we can make use of the following formula:

$\theta=(\frac{\omega_{f}+\omega_{0}}{2})t$

where θ is the total angle the basket has turned, ω is the angular velocity and t is the time.

Generally theta is written in radians and omega is written in radians per second. Now, since the revolutions are directly related to the radians and they want us to write our answer in revolutions, we can directly use the provided speeds in the formula, so we can rewrite it as:

$n=(\frac{f_{f}+f_{0}}{2})t$

where n represents the number of revolutions and f is the frequency at which the basket is turning.

The movement of the cylindrial basket can be split in two stages, when it accelerates and when it decelerates. So let's analye the first stage:

$n=(\frac{4rev/s+0}{2})(9s)=18rev$

and now let's analyze the second stage, where it decelerates, so we get:

$n=(\frac{0rev/s+4rev/s}{2})(13s)=26rev$

So now that we know how many revolutions the cylindrical basket will take as it accelerates and as it decelerates we can add them to get:

n=18rev+26rev=44rev

So the basket will turn a total of 44 revolutions during this 22s interval.

3 0

3 years ago