Find the perimeter of this please help.

Hi! how do i find surface area of a cylinder? for some reason i can’t get the right answer

asambeis [7]

$SA=2\pi r^2+2\pi rh$

Use the formula above to find the surface area of a cylinder.

For the given cylinder the given data is the height (6mi) and diameter (16mi), use the diameter to find the radius:

$\begin{gathered} r=\frac{d}{2} \\ \\ r=\frac{16mi}{2}=8mi \end{gathered}$

Surface area:

$\begin{gathered} SA=2\pi(8mi)\placeholder{⬚}^2+2\pi(8mi)(6mi) \\ SA=128\pi mi^2+96\pi mi^2 \\ SA=224\pi mi^2 \end{gathered}$ Then, the surface area of the given cylinder is: 224π square miles

5 0

8 months ago

to arrive at 2000 liters of 60% saline solution the attendant has to mix a 90% and a 40% saline solution. How many liters of eac

CaHeK987 [17]

Answer:

800 liters of 90% saline solution and 1200 liters of 40% saline solution should be used.

Step-by-step explanation:

Given:

At 2000 liters of 60% saline solution the attendant has to mix a 90% and a 40% saline solution.

Now, to find the number of liters of saline solution each should be used.

Let the liters of 90% saline solution mix be $x.$

And let the liters of 40% saline solution mix be $y.$

So, the total number of liters:

$x+y=2000.$

$y=2000-x\ \ \ ....(1)$

Now, the total percentage of saline solution:

$90\%\ of\ x+40\%\ of\ y=60\%\ of\ 2000$

$\frac{90}{100}\times x+\frac{40}{100}\times y=\frac{60}{100}\times 2000$

$0.9x+0.4y=1200$

Substituting the value of $y$ from equation (1) we get:

$0.9x+0.4(2000-x)=1200$

$0.9x+800-0.4x=1200$

$0.5x+800=1200$

Subtracting both sides by 800 we get:

$0.5x=400$

Dividing both sides by 0.5 we get:

$x=800.$

The liters of 90% saline solution mix = 800.

Now, substituting the value of $x$ in equation (1) to get the liters of 40% saline solution:

$y=2000-x$

$y=2000-800$

$y=1200.$

Thus, the liters of 40% saline solution = 1200.

Therefore, 800 liters of 90% saline solution and 1200 liters of 40% saline solution should be used.

8 0

3 years ago

Help brainiest answer to whoever is correct

Effectus [21]

Answer:

56 degrees

Step-by-step explanation:

3 0

2 years ago

Read 2 more answers

The average score of all golfers for a particular course has a mean of 75 and a standard deviation of 4. Suppose 64 golfers play

Vilka [71]

Answer:

0.0228 = 2.28% probability that the average score of the 64 golfers exceeded 76.

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.

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 $s = \frac{\sigma}{\sqrt{n}}$ .