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3 years ago

Yo can someone help me with this? (Links = report)

Mathematics

1 answer:

Troyanec [42]3 years ago

7 0

Answer:

Step-by-step explanation:

12.6 divided by pi= 4.01

sqaure root of 4 is 2

You might be interested in

A varies inversely with the square of r and when r = 4, A = 75. Find r when A = 48 r=

egoroff_w [7]

Answer:

r = 3.2

Step-by-step explanation:

If A varies inversely with the square of r, then A = kr^2

75 = k*4^2 = 16k

k = 75/16

Now A = (75/16)*r^2

48 = (75/16)*r^2

r^2 = 48(16/75) = 256/25

r = $\sqrt{\frac{256}{25} }$ = 16/5 = 3.2

7 0

3 years ago

What is the area of this plz help

statuscvo [17]

Answer:

(1/2×20×20)+(20×20)

200+400

600cm²

3 0

3 years ago

Please help hurry!!!!!!

d1i1m1o1n [39]

Answer:

136

Step-by-step explanation:

8 0

3 years ago

Two mechanics worked on a car. The first mechanic worked for 10 hours, and the second mechanic worked for 15 hours. Together the

kompoz [17]

When you are looking for the answer in this type of scenario you do.
I=PRT (interest = price•rate•time)

I = $1900•$155•25 (you add the two times)
I = $7,362,500

Hope this helps.

4 0

3 years ago

Read 2 more answers

The state education commission wants to estimate the fraction of tenth grade students that have reading skills at or below the e

kow [346]

Answer:

The 80% confidence interval for the population proportion of tenth graders reading at or below the eighth grade level is (0.149, 0.207).

Step-by-step explanation:

In a sample with a number n of people surveyed with a probability of a success of $\pi$ , and a confidence level of $1-\alpha$ , we have the following confidence interval of proportions.

$\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}$

In which

z is the zscore that has a pvalue of $1 - \frac{\alpha}{2}$ .

Suppose a sample of 292 tenth graders is drawn. Of the students sampled, 240 read above the eighth grade level.

So 292 - 240 = 52 read below or at eight grade level, and that $n = 292, \pi = \frac{52}{292} = 0.178$

80% confidence level

So $\alpha = 0.2$ , z is the value of Z that has a pvalue of $1 - \frac{0.2}{2} = 0.9$ , so $Z = 1.28$ .

The lower limit of this interval is:

$\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.178 - 1.28\sqrt{\frac{0.178*0.822}{292}} = 0.149$

The upper limit of this interval is:

$\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.178 + 1.28\sqrt{\frac{0.178*0.822}{292}} = 0.207$

The 80% confidence interval for the population proportion of tenth graders reading at or below the eighth grade level is (0.149, 0.207).

3 0

3 years ago