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3 years ago

You have 314 feet of fencing to builf a circular sheep pen. What is the largest diameter pen you can build? Use π=3.13

1 answer:

7 0

$\bf \textit{circumference/perimeter of a circle}\\\\ C=\pi d~~ \begin{cases} d=diameter\\[-0.5em] \hrulefill\\ C=314 \end{cases}\implies 314=\pi d\implies \cfrac{314}{\pi }=d \\\\\\ \stackrel{\textit{using }\pi =3.14}{\cfrac{314}{3.14}=d}\implies \cfrac{314}{~~\frac{314}{100}~~}=d\implies \cfrac{\underline{314}}{1}\cdot \cfrac{100}{\underline{314}}=d\implies \boxed{100=d}$

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Can someone please help me

Alina [70]

Yes with what ? are u single ?

5 0

2 years ago

Two marathon runners run the full distance of the marathon, approximately 26 miles, in 4 hours.

xxTIMURxx [149]

Answer:

6.5 miles in 1 hour and they will run 75% of the full distance in 1 hour.

Step-by-step explanation:

The distance covered by two marathon runners = 26 miles

They takes 4 hours

We need to find how many miles did they run in 1 hour

In 4 hour, the distance covered is 26 miles

To find distance covered in 1 hour, divide 26 by 4 such that.

$d=\dfrac{26}{4}\\\\d=6.5\ \text{miles/hour}$

So, they will cover 6.5 miles in 1 hour.

For percentage,

$\%=\dfrac{26-6.5}{26}\times 100\\\\=75\%$

So, they will run 75% of the full distance in 1 hour.

8 0

2 years ago

The width of a rectangle is 6 less than half the length. If x represents the length, which equation could be used to find the wi

Shtirlitz [24]

Answer:

C. y=1/2x-6

Step-by-step explanation:

The correct answer is C. y=1/2x-6.

If we are finding 1/2 of the length, and the length is represented by x, than we would have 1/2x.

It also says 6 less than halve of the length, so we would represent that as 1/2x-6, and that shows us the proper equation to find the width.

Hope this helps!

5 0

2 years ago

Please help with imaginary numbers worksheet!

mihalych1998 [28]

Problem 5

<h3>Answer: 6i</h3>

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

Explanation:

We have these four identities

i^0 = 1
i^1 = i
i^2 = -1
i^3 = -i

Notice how computing i^4 leads us back to 1. So i^4 = i^0. The pattern repeats every 4 terms. So we divide the exponent by 4 and look at the remainder. We ignore the quotient entirely. We can see that 28/4 = 7 remainder 0. Meaning that i^28 = i^0 = 1.

We can think of it like this if you wanted

i^28 = (i^4)^7 = 1^7 = 1

Then the sqrt(-36) becomes 6i

So overall, we end up with the final answer of 6i

=============================================

Problem 6

<h3>Answer: -3i</h3>

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

Explanation:

We'll use the ideas mentioned in problem 5

46/4 = 11 remainder 2

i^46 = i^2 = -1

sqrt(-9) = 3i

The two outside negative signs cancel out, but there's still a negative from -1 we found earlier. So we end up with -3i

In other words, here is one way you could write out the steps

$-i^{46}*-\sqrt{-9}\\\\-i^{2}*-3i\\\\i^{2}*3i\\\\-1*3i\\\\-3i\\\\$

=============================================

Problem 7

<h3>Answer: -1</h3>

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

Work Shown:

i^10 = i^2 because 10/4 = 2 remainder 2

i^19 = i^3 because 19/4 = 4 remainder 3

i^7 = i^3 because 7/4 = 1 remainder 3

Again, all we care about are the remainders.

$i^{10}+i^{19} - i^{7}\\\\i^{2}+i^{3} - i^{3}\\\\i^{2}\\\\-1$

=============================================

Problem 8

<h3>Answer: -1 + i</h3>

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

Work Shown:

i^22*i^6 = i^(22+6) = i^28

Earlier in problem 5, we found that i^28 = i^0 = 1

So,

$i^1 - \left(i^{22}*i^{6}\right)\\\\i^1 - i^{28}\\\\i^1 - i^{0}\\\\i - 1\\\\-1+i$

8 0

2 years ago

Read 2 more answers

Two brands of AAA batteries are tested in order to compare their voltage. The data summary can be found below. Find the 93% conf

kobusy [5.1K]

Answer:

$(\bar X_1 -\bar X_2) \pm z_{\alpha/2} \sqrt{\frac{s^2_1}{n_1}+\frac{s^2_}{n_2}}$

And replacing we got:

$(9.2 -8.8) - 1.811 \sqrt{\frac{0.3^2}{27}+\frac{0.1^2}{30}}= 0.2903$

$(9.2 -8.8) + 1.811 \sqrt{\frac{0.3^2}{27}+\frac{0.1^2}{30}}= 0.5097$

And the confidence interval for the difference of means would be given by:

$0.2903 \leq \mu_1 -\mu_2 \leq 0.5097$

Step-by-step explanation:

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".

We have the following data given:

$\bar X_1 = 9.2 , \bar X_2 = 8.8, \sigma_1= 0.3, n_1 = 27, \sigma_2 = 0.1, n_2 = 30$

In order to find the critical value we need to take in count that we are finding the interval for a proportion, so on this case we need to use the z distribution. Since our interval is at 93% of confidence, our significance level would be given by $\alpha=1-0.93=0.07$ and $\alpha/2 =0.035$ . And the critical value would be given by:

$z_{\alpha/2}=-1.811, z_{1-\alpha/2}=1.811$

The confidence interval is given by:

$(\bar X_1 -\bar X_2) \pm z_{\alpha/2} \sqrt{\frac{s^2_1}{n_1}+\frac{s^2_}{n_2}}$

And replacing we got:

$(9.2 -8.8) - 1.811 \sqrt{\frac{0.3^2}{27}+\frac{0.1^2}{30}}= 0.2903$

$(9.2 -8.8) + 1.811 \sqrt{\frac{0.3^2}{27}+\frac{0.1^2}{30}}= 0.5097$

And the confidence interval for the difference of means would be given by:

$0.2903 \leq \mu_1 -\mu_2 \leq 0.5097$

4 0

3 years ago