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2 years ago

Math stuff who ever answers right gets brainlest answer

Mathematics

1 answer:

lyudmila [28]2 years ago

6 0

Answer:

Median is 83

Range: 61

Step-by-step explanation:

The median is the number in the middle. The range is the max. number subtracted from the min number.

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Which number is closest to the

disa [49]

I think it is D
Hope my answer help you?

5 0

2 years ago

Read 2 more answers

Help! complete the table with the missing measurements. the perimeter is 40ft is that helps

Solnce55 [7]

therer sorry for the cropped pic btw lol

8 0

2 years ago

In a recent year, Washington State public school students taking a mathematics assessment test had a mean score of 276.1 and a s

Oksi-84 [34.3K]

Answer:

a) $\mu_{\bar x} =\mu = 276.1$

$\sigma_{\bar x} =\frac{\sigma}{\sqrt{n}}=\frac{34.4}{\sqrt{64}}=4.3$

b) From the central limit theorem we know that the distribution for the sample mean $\bar X$ is given by:

$\bar X \sim N(\mu=276.1, \frac{\sigma}{\sqrt{n}}=4.3)$

c) $P(\bar X \geq 285)=P(Z\geq \frac{285-276.1}{4.3}=2.070)$

$P(Z\geq2.070)=1-P(Z$

Step-by-step explanation:

Let X the random variable the represent the scores for the test analyzed. We know that:

$\mu=E(X) = 276.1 , \sigma=Sd(X) = 34.4$

And we select a sample size of 64.

The central limit theorem states that "if we have a population with mean μ and standard deviation σ and take sufficiently large random samples from the population with replacement, then the distribution of the sample means will be approximately normally distributed. This will hold true regardless of whether the source population is normal or skewed, provided the sample size is sufficiently large".

Part a

For this case the mean and standard error for the sample mean would be given by:

$\mu_{\bar x} =\mu = 276.1$

$\sigma_{\bar x} =\frac{\sigma}{\sqrt{n}}=\frac{34.4}{\sqrt{64}}=4.3$

Part b

From the central limit theorem we know that the distribution for the sample mean $\bar X$ is given by:

$\bar X \sim N(\mu=276.1, \frac{\sigma}{\sqrt{n}}=4.3)$

Part c

For this case we want this probability:

$P(\bar X \geq 285)$

And we can use the z score defined as:

$z=\frac{\bar x -\mu}{\sigma_{\bar x}}$

And using this we got:

$P(\bar X \geq 285)=P(Z\geq \frac{285-276.1}{4.3}=2.070)$

And using a calculator, excel or the normal standard table we have that:

$P(Z\geq2.070)=1-P(Z$

8 0

3 years ago

The population of mosquitoes in a certain area increases at a rate proportional to the current population, and in the absence of

Nesterboy [21]

Answer:

$P=400000(2^t)-40000t$

Step-by-step explanation:

The initial number of mosquitoes is 400000, and they double each day. This represents an exponential growth equation. If t represent days and P represent the population of the mosquitoes, hence this can be represented by the equation:

$P=400000(2^t)$

Also, the predators eat the mosquitoes at a rate of 40,000 mosquitoes/day. This means that each day, the mosquitoes reduce by 40000t, therefore this can be represented by:

$P=400000(2^t)-40000t$

8 0

3 years ago

16x 2 + 8x - 15 Mathematics?

Gala2k [10]

If you're factoring, your answer is

(4x - 3)(4x + 5)

You'll work it out this way:

16x^2 + 8x - 15

Since there's no GCF here, you multiply the first and third terms, giving you -240. Your next step is to find two numbers that have a sum of 8 and a product of -240. These numbers are 20 and -12. Plug those in and you've got:

16x^2 + 20x - 12x - 15

From here you divide it into two binomials. These are (16x^2 + 20x) and (-12x - 15).
When you take out the greatest common factors (4x and -3), they become:

4x(4x + 5) - 3(4x + 5)

Then you group what's outside of the parentheses together (4x - 3)
And bring what's inside of the parentheses down (4x + 5).
This brings your answer to

(4x - 3)(4x + 5)

5 0

3 years ago

Math stuff who ever answers right gets brainlest answer​

Math stuff who ever answers right gets brainlest answer