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4 years ago

PLEASE HELP IF MORE THAN ONE PERSON ANSWERS ILL GIVE BRAINLIEST!!!

Mathematics

1 answer:

lina2011 [118]4 years ago

6 0

Answer:

see explanation

Step-by-step explanation:

The area of the shaded portion is the area of the outer circle subtract the area of the inner circle

area of larger circle = πr² ← r is the radius = 11

area = π × 11² = 121π

area of smaller circle = πr² ← r = 9

area = π × 9² = 81π

-----------------------------------------

shaded area = 121π - 81π = 40π m² ≈ 126 m²

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Two equation Ax+By=1 and (3,-1)(-2,-2). Find A and B

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IT IS Biodarmate physical access process in great Aphrodite in which is will be used when both the variable size will be multiplied with both

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3 years ago

If two boxes of cereal and a jug of milk cost $8.50, and three boxes of cereal and two jugs of milk cost $14.00, how much does a

Citrus2011 [14]

Answer:

Step-by-step explanation:

Let c represent the cost of a box of cereal and let m represent the cost of a jug of milk.

Create a system of equations:

2c + m = 8.5

3c + 2m = 14

Solve by elimination by multiplying the top equation by -2:

-4c - 2m = -17

3c + 2m = 14

Add them together and solve for c:

-c = -3

c = 3

So, a box of cereal costs $3

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3 years ago

A sanitation department is interested in estimating the mean amount of garbage per bin for all bins in the city. In a random sam

soldi70 [24.7K]

Answer:

a) $52.8-2.02\frac{3.9}{\sqrt{40}}=51.554$

b) $52.8+2.02\frac{3.9}{\sqrt{40}}=54.046$

c) $52.8-2.71\frac{3.9}{\sqrt{40}}=51.129$

d) $52.8+2.71\frac{3.9}{\sqrt{40}}=54.471$

e) Yes, depends of the confidence level.

At 95 % of confidence the value 54.1985 pounds is not included on the interval. At 5% of significance the statement is FALSE.

At 99 % of confidence the value 54.1985 pounds is included on the interval. So at 1% of significance the statement is TRUE.

Step-by-step explanation:

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".

$\bar X =52.8$ represent the sample mean for the sample

$\mu$ population mean (variable of interest)

s=3.9 represent the sample standard deviation

n=40 represent the sample size

a) What is the lower limit of the 95% interval? Give your answer to three decimal places

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

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

In order to calculate the mean and the sample deviation we can use the following formulas:

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

$df=n-1=40-1=39$

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(0.025,39)".And we see that $t_{\alpha/2}=2.02$

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

$52.8-2.02\frac{3.9}{\sqrt{40}}=51.554$

b) What is the upper limit of the 95% interval? Give your answer to three decimal places

$52.8+2.02\frac{3.9}{\sqrt{40}}=54.046$

So on this case the 95% confidence interval would be given by (51.554;54.046)

c) What is the lower limit of the 99% interval? Give your answer to three decimal places

Since the Confidence is 0.99 or 99%, the value of $\alpha=0.01$ and $\alpha/2 =0.005$ , and we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-T.INV(0.005,39)".And we see that $t_{\alpha/2}=2.71$

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

$52.8-2.71\frac{3.9}{\sqrt{40}}=51.129$

d) What is the upper limit of the 99% interval? Give your answer to three decimal places

$52.8+2.71\frac{3.9}{\sqrt{40}}=54.471$

So on this case the 99% confidence interval would be given by (51.129;54.471)

e) Consider the claim that the mean amount of garbage per bin is 54.1985 pounds. Is the following statement true or false? The decision about the claim would depend on whether we use a 95% or 99% confidence interval: True/False

Yes, depends of the confidence level.

At 95 % of confidence the value 54.1985 pounds is not included on the interval. At 5% of significance the statement is FALSE.

At 99 % of confidence the value 54.1985 pounds is included on the interval. So at 1% of significance the statement is TRUE.

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4 years ago

A 2-gallon container of laundry detergent costs $19.68. what is the price per pint?

BigorU [14]

Answer:

0.81

Step-by-step explanation:

There are 8 pints = 1 gallon

8 times 2= 16/19.68=0.813

each pint is 0.81 cents

6 0

4 years ago

Can someone please help me with this?

aivan3 [116]

Answer:

Answer Option C

Step-by-step explanation:

They make a big plus sign, PLUS=PERPENDICULAR

4 0

2 years ago