Twice age of 63???????????????????????????

An engineer is going to redesign an ejection seat for an airplane. The seat was designed for pilots weighing between 130 lb and

egoroff_w [7]

Answer:

a) $P(140$

$P(0.036$

b) $P(140< \bar X$

Step-by-step explanation:

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".

Part a

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:

$X \sim N(139,28.1)$

Where $\mu=139$ and $\sigma=28.1$

We are interested on this probability

$P(140$

And the best way to solve this problem is using the normal standard distribution and the z score given by:

$z=\frac{x-\mu}{\sigma}$

If we apply this formula to our probability we got this:

$P(140$

And we can find this probability like this:

$P(0.036$

And in order to find these probabilities we can find tables for the normal standard distribution, excel or a calculator.

$P(0.036$

Part b

For this case we select a sample size of n =32. Since the distribution for X is normal then the distribution for the sample mean $\bar X$ is given by:

$\bar X \sim N(\mu=139, \frac{\sigma}{\sqrt{n}}=\frac{28.1}{\sqrt{32}}=4.97)$

And the new z score would be:

$Z=\frac{\bar X -\mu}{\sigma_{\bar x}}$

$P(140< \bar X$

5 0

3 years ago

How do i do this i'm really confused it's nothing i've done before

laila [671]

What is the question pls so I might be able to help

6 0

2 years ago

I’m thinking the answer should be B right ??

laiz [17]

Hello!

The formula for the volume of a sphere is $\frac{4}{3} \pi r$ ³.

Let's plug in our radius.

$\frac{4}{3} \pi (1,000)$

As we are not looking for an exact answer,we can look for an answer in terms of pi. Maybe we could multiply our fraction by 1,000.

$\frac{4000}{3} \pi$

Therefore, our answer is D.

I hope this helps!

7 0

3 years ago

Elisa puts $1,000 into each of 2 bank accounts.

Dafna1 [17]

Answer:

How much money will be in Account A at the end of 3 years? $ ⇒ 1092.73

How much money will be in Account B at the end of 3 years? $112

Step-by-step explanation:

8 0

2 years ago

Read 2 more answers

In the straightedge and compass construction of the parallel line below, which of the following reasons can you use to prove tha

Eva8 [605]

Answer:

D.

Step-by-step explanation:

Lines EG and CD are cut by transversal CF.

By construction, ∠FEG=∠FCD. These two angles are corresponding angles.

Since two corresponding angles are congruent, then lines EG and CD are parallel (by converse of the corresponding angles postulate).

Converse of the Corresponding Angles Postulate: If the corresponding angles formed by two lines and a transversal are congruent, then lines are parallel.

3 0

2 years ago