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4 years ago

PLSSSS HELPPP MEEEEEE

Mathematics

1 answer:

labwork [276]4 years ago

5 0

Circumference of the smaller circle, using $C = \pi d$ , is approximately equal to 18.85 (I used the high floating point precision approximation of pi my calculator has in memory, then rounded to 2 decimal points.)

Using the formula $S = 0.2L$ , which in English says "the smaller circle's circumference is equal to 20% of the larger circle's", we can substitute the known value S: $18.85 = 0.2L$ and solve for L: $\frac{18.5}{0.2} = L, L = 92.5$ .

So the larger circle has a circumference approximately equal to 92.5 units.

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Ludwig takes a job at a large bakery chain. After he is hired, he mentions that he practices a particular religion. The manager

aliya0001 [1]

The correct answer is the civil rights act

7 0

3 years ago

The health of the bear population in a park is monitored by periodic measurements taken from anesthetized bears. A sample of the

Vikki [24]

Answer:

$182.167-2.03\frac{114.05}{\sqrt{36}}=143.580$

$182.167+2.03\frac{114.05}{\sqrt{36}}=220.754$

So on this case the 95% confidence interval would be given by (143.580;220.754)

Step-by-step explanation:

Assuming the following dataset:

77, 349,417,349, 167 , 225, 265, 360,205

145,335,40,139, 177,108, 163, 202, 22

123,439, 125,135, 86,43, 217,49, 156

119,178, 151, 61, 350, 312, 91, 89,89

We can calculate the sample mean with the followinf formula:

$\bar X = \frac{\sum_{i=1}^n X_i}{n}= 182.167$

And the sample deviation with:

$s = \sqrt{\frac{\sum_{i=1}^n (X_i-\bar X)^2}{n-1}}=114.05$

The sample size on this case is n =36.

Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

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".

$\bar X=182.167$ represent the sample mean

$\mu$ population mean (variable of interest)

s=114.05 represent the sample standard deviation

n=36 represent the sample size

The confidence interval for the mean is given by the following formula:

$\bar X \pm t_{\alpha/2}\frac{s}{\sqrt{n}}$ (1)

The point estimate of the population mean is $\hat \mu = \bar X =182.167$

In order to calculate the critical value $t_{\alpha/2}$ we need to find first the degrees of freedom, given by:

$df=n-1=36-1=35$

Since the Confidence is 0.95 or 95%, the value of $\alpha=0.05$ and $\alpha/2 =0.025$ , and we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-T.INV(0.025,35)".And we see that $t_{\alpha/2}=2.03$

Now we have everything in order to replace into formula (1):

$182.167-2.03\frac{114.05}{\sqrt{36}}=143.580$

$182.167+2.03\frac{114.05}{\sqrt{36}}=220.754$

So on this case the 95% confidence interval would be given by (143.580;220.754)

5 0

3 years ago

Starting at home, Omar traveled uphill to the gift store for 30 minutes at just 10 mph. He then traveled back home along the sam

hichkok12 [17]

I guess you want to find the average speed for the whole journey

average speed = distance travelled / time

the distance from home to the shop = speed * time = 0.5*10 = 5 miles

time for travelling back = distance / speed = 5/30 = 1/6 hours

average speed for whole journey = 10 / (1/2 + 1/6) = 10 * 3 / 2 = 15 mph

4 0

3 years ago

3. 5 bananas cost $2. At this rate, how much do 4 bananas cost?

Annette [7]

Answer:

$1.60

Step-by-step explanation:

Write out a proportion.

5 bananas/$2 = 4 bananas/$x

Simplify the proportion, by cross multiplying.

2 times 4 equals 8, then divide 8 by 5, which will give you our variable x.

8/5 is the same as 1.60, so the cost of 4 bananas will cost $1.60.

Hope this helped,

Philip

Brainliest always appreciated! <3

6 0

3 years ago

Which polynomial represents the difference below? 10x^8 + 11x^6 - 2x + 5 - (8x8 + 6x7 - 5)

katrin2010 [14]

Answer:

$2x^8-6x^7+11x^6-2x+10$

Step-by-step explanation:

To find: $10x^8+11x^6-2x+5-(8x^8+6x^7-5)$

Solution:

Like terms refer to terms with same variables and same powers.

Two like terms can be added or subtracted.

Consider the following expression:

$10x^8+11x^6-2x+5-(8x^8+6x^7-5)=10x^8+11x^6-2x+5-8x^8-6x^7+5\\=(10-8)x^8-6x^7+11x^6-2x+(5+5)\\=2x^8-6x^7+11x^6-2x+10$

(Here, like terms are added or subtracted)

7 0

3 years ago