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3 years ago

I need to know the surface area of these

Mathematics

1 answer:

anastassius [24]3 years ago

6 0

9514 1404 393

Answer:

245 cm²

Step-by-step explanation:

The surface area of a cone is given by ...

SA = πr(r +s) . . . . where r is the radius, and s is the slant height

Filling in the given values, we have ...

SA = (3.14)(3 cm)(3 cm +23 cm) = (3.14)(3)(26) cm² ≈ 245 cm²

The surface area of the cone is about 245 cm².

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Answer the question to become brainliest

marishachu [46]

Answer:

2406.17 cm³

Step-by-step explanation:

The following data were obtained from the question:

Height (h) = 24.4 cm

Base length (L) = 17.2 cm

Volume (V) =?

Next, we shall determine the base area of the pyramid. This can be obtained as follow:

Base length (L) = 17.2 cm

Base area (B) =.?

B = L × L

B = 17.2 × 17.2

B = 295.84 cm²

Finally, we shall determine the volume of the pyramid. This can be obtained as follow:

Height (h) = 24.4 cm

Base area (B) = 295.84 cm²

Volume (V) =?

V = ⅓Bh

V = ⅓ × 295.84 × 24.4

V = 2406.17 cm³

Thus, we volume of the pyramid is 2406.17 cm³

7 0

3 years ago

In a clinical test with 2161 subjects, 1214 showed improvement from the treatment. Find the margin of error for the 95% confiden

Vlad [161]

Answer:

The margin of error for the 95% confidence interval used to estimate the population proportion is of 0.0209.

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 z-score that has a p-value of $1 - \frac{\alpha}{2}$ .

The margin of error is of:

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

In a clinical test with 2161 subjects, 1214 showed improvement from the treatment.

This means that $n = 2161, \pi = \frac{1214}{2161} = 0.5618$

95% confidence level

So $\alpha = 0.05$ , z is the value of Z that has a p-value of $1 - \frac{0.05}{2} = 0.975$ , so $Z = 1.96$ .

Margin of error:

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

$M = 1.96\sqrt{\frac{0.5618*0.4382}{2161}}$

$M = 0.0209$

The margin of error for the 95% confidence interval used to estimate the population proportion is of 0.0209.

4 0

3 years ago

A standard American Eskimo dog has a mean weight of 30 pounds with a standard deviation of 2 pounds. Assuming the weights of sta

nalin [4]

Answer:

Option 2 - Approximately 24–36 pounds

Step-by-step explanation:

Given : A standard American Eskimo dog has a mean weight of 30 pounds with a standard deviation of 2 pounds. Assuming the weights of standard Eskimo dogs are normally distributed.

To find : What range of weights would 99.7% of the dogs have?

Solution :

The range of 99.7% will lie between the mean ± 3 standard deviations.

We have given,

Mean weight of Eskimo dogs is $\mu=30$