if anyone gose and answers my 3 questions I just put up ill give you 40 points and I need them to be right

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

3/4 = j−12.<br><br> Algebra

Studentka2010 [4]

First, we simplify this to 3/4-j/12=0. 4/4=1 so we do, -j=-51/4*-1. Therefore, the answer is j=51/4. Hoped I helped. :)

6 0

3 years ago

Read 2 more answers

PLEASE HELP ME ASAP!!!

Leokris [45]

Answer:

m(x)= 0 when X= 3

Step-by-step explanation:

2*3=6

6-6=0

For (2x-6)

3-4=-1

So -1*0=0

it can also be look at like this (0,-1)

7 0

3 years ago

What is 27.35 expressed as a mixed number?

zheka24 [161]

Firstly, you know you have 27 (35/100)

Make this an improper fraction. 2735/100

Simplify this as much as you can. 547/20

Find how many times 20 will go into 540, and use the 7/20 as the fraction part of your mixed number.

Now, make as many whole as you can and states your remaining. 27 7/20

4 0

3 years ago

What is the Greatest common factor of 18x^2 and 36x

loris [4]

For this case we have that by definition, the Greatest Common Factor or GFC of two or more numbers, is the largest number that divides them without leaving residue.

So:

We look for the factors of 18 and 36:

18: 1,2,3,6,9,18

36: 1, 2,3,4, 6,9,18 ...

Thus, the GFC of both numbers is 18.

Then, the GFC of $18x ^ 2$ and $36x$ is:

$18x$

Answer:

$18x$

6 0

3 years ago