You start driving west for 20 miles, turn left, and drive south for another 14 miles. At

To decrease the impact on the environment, factory chimneys must be high enough to allow pollutants to dissipate over a larger a

Komok [63]

Answer:

The probability hat the sample mean height for the 40 chimneys is greater than 102 meters is 0.1469.

Step-by-step explanation:

Let the random variable X be defined as the height of chimneys in factories.

The mean height is, μ = 100 meters.

The standard deviation of heights is, σ = 12 meters.

It is provided that a random sample of n = 40 chimney heights is obtained.

According to the Central Limit Theorem if we have an unknown population with mean μ and standard deviation σ and appropriately huge random samples (n > 30) are selected from the population with replacement, then the distribution of the sample means will be approximately normally distributed.

Then, the mean of the distribution of sample means is given by,

$\mu_{\bar x}=\mu$

And the standard deviation of the distribution of sample means is given by,

$\sigma_{\bar x}=\frac{\sigma}{\sqrt{n}}$

Since the sample selected is quite large, i.e. n = 40 > 30, the central limit theorem can be used to approximate the sampling distribution of sample mean heights of chimneys.

$\bar X\sim N(\mu_{\bar x},\ \sigma^{2}_{\bar x})$

Compute the probability hat the sample mean height for the 40 chimneys is greater than 102 meters as follows:

$P(\bar X>102)=P(\frac{\bar X-\mu_{\bar x}}{\sigma_{\bar x}})>\frac{102-100}{12/\sqrt{40}})$

$=P(Z>1.05)\\=1-P(Z$

*Use a z-table fr the probability.

Thus, the probability hat the sample mean height for the 40 chimneys is greater than 102 meters is 0.1469.

8 0

3 years ago

Merlin wants to make more money selling fake beards this month than he did last month. All black beards in his shop cost the sam

sukhopar [10]

We know that all black beards cost the same money

And all red beards cost $25

And B represents number of black beards

And R represents number of red beards

We have been given the inequality 20B+25R > 350 to show the target for this month.

The above inequality shows that Merlin needs to make more than 350, hence he made 350 last month

Further, it shows that B has been multiplied by 20, hence the black beard's cost was 20

8 0

3 years ago

Read 2 more answers

what is another way to write 297.3. Fill in: 2hundreds, 9tens, 5 ones + __________tenths I tried 2.3, but was told that was inco

Schach [20]

Maybe it is 23 tenths ???

7 0

3 years ago

Every time Luisa bakes a batch of brownies she uses 1/2 cup of chocolate if she has 3/2 cups of chocolate remaining how many bat

kakasveta [241]

Answer:

she can make 4 batches of brownies

Step-by-step explanation:

since she already made a batch of brownie with 1/2 cup and she has 3/2 cups left, that means she can make 3 more

3+1=4

hope this helps

3 0

3 years ago

Does anyone know how tj do this (trig)

Crank

Answer:

x = 5

Step-by-step explanation:

NOTE: THE 2 SIDES ARE THE SAME LENGTH

THEY HAVE TO BE SMALLER THEN 10

So 10/2 = 5

x = 5

Please mark as brainliest

Have a great day, be safe and healthy

Thank u

XD

8 0

3 years ago