All categories

3 years ago

If the area of a circle measures 25π cm2, what is the circumference of the circle in terms of π?

2 answers:

5 0

Two formulas here:

Area = πr²

Circumference = 2<span>πr

So first we solve for r from area:

25</span>π = πr²

25 = r²

r = 5

So we know that radius is 5 cm.

Now substitute r to 5 in circumference formula:

C = 2π(5) = 10π

Final answer: 10π cm

Hope this helps.

zhannawk [14.2K]3 years ago

5 0

Answer:

10 $\pi$ cm

Step-by-step explanation:

You might be interested in

A manager of a grocery store wants to determine if consumers are spending

ololo11 [35]

Answer:

1. The error in the assumption is taking the sample mean, $\bar x$ , as being equal to the population mean, μ

2. To correct the error, the manager will need to generate the confidence interval based on the population standard deviation on the acceptable values of the mean using the following relation;

$CI=\bar{x}\pm z\frac{\sigma}{\sqrt{n}}$

Step-by-step explanation:

We note that from the central limit theorem as the size of the sample, n, becomes more and more larger, the mean of the sample, $\bar x$ , approaches that of the population mean, μ, therefore as the grocery store manager uses the sample mean as the population mean's point estimate an error will be observed based on the size of the sample compared to the population, where the difference between the two means (the population mean and the sample mean) is $\left | \bar{x} - \mu \right |$

1. The error in the assumption is taking the sample mean, $\bar x$ , as being equal to the population mean, μ

2. To correct the error, the manager will need to generate the confidence interval based on the population standard deviation on the acceptable values of the mean using the following relation;

$CI=\bar{x}\pm z\frac{\sigma}{\sqrt{n}}$

Where:

σ = Population standard deviation = $30

z = z value at 95% confidence level = 1.96

$\bar x$ = Sample mean $160

n = Sample size = 10

Plugging in the values, we have;

$141.4 < $\bar x$ < $178.6

Hence the expected value of the mean should be between $141.4 and $178.6.

7 0

3 years ago

The perimeter of the figure to the right, made up of identical squares, is equal to 56 cm. What is the area of the figure?

Mamont248 [21]

The area of the square will be 196cm².

<h3>How to calculate the area?</h3>

It should be noted that the perimeter of a square is the addition of all its sides. Therefore, the length of the side will be:

= 56/4

= 14

Therefore, the area of the figure will be:

= 14²

= 14 × 14

= 196cm²

Learn more about area on:

brainly.com/question/25292087

#SPJ1

4 0

2 years ago

At 9:00 pm bob leaves his home and starts walking to the bus stop at a constant speed of 9.3 feet per second. bob's house is 432

klio [65]

a. define variables for the quantities that are changing (be specific).
We define variables:
t = time in second
d = distance traveled
The variables that are changing are t and d.
As the time increases, the distance decreases.

b. what does it mean to say bob walks at a constant speed of 9.3 feet per second?
It means that for every second that passes, Bob walks 9.3 feet.

c. consider the formula d = 4320 - 9.3t i. what does t represent? ii. what does 9.3t represent? iii. what does d represent?
For this case we have:
t = represents the time in seconds
9.3t = represents the distance traveled by Bob
d = represents the distance Bob must travel to get to the bus stop.

5 0

2 years ago

Martene got a small aquarium for her birthday. The aquarium is a right rectangular prism 18.5cm long by 15cm wide. Martene put 3

natita [175]

Equation for this problem: Total 3 cubed / (L x W)

So 18.5cm x 15cm = 277.5 is the product of L and W. Now you need to devide the total by 277.5 which is 14. So the aquarium is 14 cm deep.

7 0

2 years ago

If the filling equipment is functioning properly what is the probability that the volume of oil in a randomly selected barrel wi

Sophie [7]

Answer:

$P(X>55.4)=P(\frac{X-\mu}{\sigma}>\frac{55.4-\mu}{\sigma})=P(Z>\frac{55.4-55}{0.5})=P(Z>0.8)$

$P(Z>0.8)=1-P(Z\leq 0.8)$

$P(Z>0.8)=1-0.788=0.212$

Step-by-step explanation:

Assuming this previous info : "Trucks carry barrels of crude oil from a port in Texas to a distributer in New Mexico on long trailers. Filling equipment is used to fill the barrels with the oil. When functioning properly, the actual volume of oil loaded into each barrel by the filling equipment at the port is approximately normally distributed with a mean of 55 gallons and a standard deviation of 0.5 gallons. If the mean is greater than 55.4 gallons, the filling mechanism is overfilling."

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".

Solution to the problem

Let X the random variable that represent the amount filling of a population, and for this case we know the distribution for X is given by:

$X \sim N(55,0.5)$

Where $\mu=55$ and $\sigma=0.5$

We are interested on this probability

$P(X>55.4)$

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:

$P(X>55.4)=P(\frac{X-\mu}{\sigma}>\frac{55.4-\mu}{\sigma})=P(Z>\frac{55.4-55}{0.5})=P(Z>0.8)$

And we can find this probability using the complement rule:

$P(Z>0.8)=1-P(Z\leq 0.8)$

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

$P(Z>0.8)=1-0.788=0.212$

8 0

3 years ago