Help!! with explanation plss...

An electrician leans an extension ladder against the outside wall of a house so that it reaches an electric box 22 feet up. The

jeka57 [31]

The ladder and the outside wall form a right triangle

The length of the ladder is 97.8 feet

<h3>How to determine the length of the ladder?</h3>

The given parameters are:

Distance (B) = 22 feet

Angle of elevation (θ) = 77 degrees

The length (L) of the ladder is calculated using the following cosine ratio

cos(θ) = B/L

So, we have:

cos(77) = 22/L

Make L the subject

L = 22/cos(77)

Evaluate the product

L = 97.8

Hence, the length of the ladder is 97.8 feet

Read more about right triangles at:

brainly.com/question/2437195

3 0

2 years ago

Plz help!!!! (click on the pic)

goblinko [34]

Answer:

x^2+8x

Step-by-step explanation:

instructions included above :)

7 0

4 years ago

Drake's sister Stephanie is 2 years younger than him. If the sum of Drake's age and 2 times Stephanie's age is 98, how old is St

Bogdan [553]

Answer:

S=32 D=34

Step-by-step explanation:

{-----------------VARIABLES------------}

D=Drake

S=Stephanie

TA=Total Age

{----------------GIVEN/EQUATIONS-------------}

D=S+2

TA=D+2s

{--------------SUB/SOLVE---------------}

98=D+2S

SUB FOR D

98=3S+2

96=3S

S=32

D=S+2

D=34

5 0

3 years ago

A quality-conscious disk manufacturer wishes to know the fraction of disks his company makes which are defective. Step 2 of 2 :

const2013 [10]

Answer:

The 80% confidence interval for the population proportion of disks which are defective is (0.059, 0.079).

Step-by-step explanation:

In a sample with a number n of people surveyed with a probability of a success of $\pi$ , and a confidence level of $1-\alpha$ , we have the following confidence interval of proportions.

$\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}$

In which

z is the zscore that has a pvalue of $1 - \frac{\alpha}{2}$ .

Suppose a sample of 1067 floppy disks is drawn. Of these disks, 74 were defective.

This means that $n = 1067, \pi = \frac{74}{1067} = 0.069$

80% confidence level

So $\alpha = 0.2$ , z is the value of Z that has a pvalue of $1 - \frac{0.2}{2} = 0.9$ , so $Z = 1.28$ .

The lower limit of this interval is:

$\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.069 - 1.28\sqrt{\frac{0.069*0.931}{1067}} = 0.059$

The upper limit of this interval is:

$\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.069 + 1.28\sqrt{\frac{0.069*0.931}{1067}} = 0.079$

The 80% confidence interval for the population proportion of disks which are defective is (0.059, 0.079).

7 0

3 years ago

Your consulting firm is submitting a bid for a big contract. From previous data, you know your firm has a 51% of successfully la

GREYUIT [131]

Answer:

P(S/A) = 0.6235

Step-by-step explanation:

Let's call S that you successfully bid, S' that you unsuccessfully bid, A that the agency asked for more information and A' that the agency didn't asked for more information.

So, the probability P(S/A) that the bid is successful given that the agency asks for more information is calculated as:

P(S/A) = P(S∩A)/P(A)

Where P(A) = P(S∩A) + P(S'∩A)

Then, the probability P(S∩A) that you successfully bid and the agency asked for more information is:

P(S∩A) = 0.51 * 0.7 = 0.357

Because your firm has a 51% of successfully landing the contract and if you successfully bid, then the probability the agency asks for information is 70%.

At the same way, the the probability P(S'∩A) that you unsuccessfully bid and the agency asked for more information is:

P(S'∩A) = (1-0.51) * 0.44 = 0.2156

So, P(A) and P(S/A) are equal to:

P(A) = 0.357 + 0.2156 = 0.5726

P(S/A) = 0.357/0.5726 = 0.6235

3 0

3 years ago