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2 years ago

What will be the answer?

Mathematics

1 answer:

xeze [42]2 years ago

4 0

The last row is found by adding the first 2 rows and subtracting the third row for each colum.

last number = 7 + 6 = 13-8 =5

answer: 5

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Twenty-seven minus of a number (x) is not more than 36. What is the number? A. x > 42 B. x ≥ -6 C. x < 3 D. x ≤ -6

natali 33 [55]

Answer:

Step-by-step explanation:

since it hints that it is less than we can see that B gives it to us also it can't be A cuz 42 is greater than 36

so it is B

Brain list plss

5 0

3 years ago

2) Calculate the surface<br> area of the cylinder:<br> 5 cm

AVprozaik [17]

Answer:

28π cm²

Step-by-step explanation:

The surface of a cylinder is given by the formula:

2πrh + 2πr²

where r is the radius of the base, and h is the height.

Using the image, we can find that the radius of the cylinder would be 2 cm, and the height would be 5 cm.

Now, to find the surface area of the cylinder, we would have to plug in 2 for r (the radius of the base) and 5 for h (the height of the cylinder) into the formula for the surface area of a cylinder.

Now we plug in 2 for r and 5 for h for the equation for the surface area of a cylinder:

2π(2)(5) + 2π(2)² = 20π + 2π(4) = 20π + 8π = 28π

Remember, the radius and the height are given to us in cm, and w are solving for surface area, so the answer should be in cm² (square centimeters).

The surface area of the cylinder would be 28π cm².

28π cm² would be an exact answer. For the approximate answer, plug in 3.14 (most math classes use 3.14 to approximate π) for π.

I hope you find this helpful. :)

5 0

3 years ago

A researcher reports survey results by stating that the standard error of the mean is 25 the population standard deviation is 40

bezimeni [28]

Answer:

a) A sample of 256 was used in this survey.

b) 45.14% probability that the point estimate was within ±15 of the population mean

Step-by-step explanation:

This question is solved using the normal probability distribution and the central limit theorem.

Normal probability distribution

When the distribution is normal, we use the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

Central Limit Theorem

The Central Limit Theorem estabilishes that, for a normally distributed random variable X, with mean $\mu$ and standard deviation $\sigma$ , the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean $\mu$ and standard deviation $s = \frac{\sigma}{\sqrt{n}}$ .

For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.

a. How large was the sample used in this survey?

We have that $s = 25, \sigma = 400$ . We want to find n, so:

$s = \frac{\sigma}{\sqrt{n}}$

$25 = \frac{400}{\sqrt{n}}$

$25\sqrt{n} = 400$

$\sqrt{n} = \frac{400}{25}$

$\sqrt{n} = 16$

$(\sqrt{n})^2 = 16^2[tex][tex]n = 256$

A sample of 256 was used in this survey.

b. What is the probability that the point estimate was within ±15 of the population mean?

15 is the bounds with want, 25 is the standard error. So

Z = 15/25 = 0.6 has a pvalue of 0.7257

Z = -15/25 = -0.6 has a pvalue of 0.2743

0.7257 - 0.2743 = 0.4514

45.14% probability that the point estimate was within ±15 of the population mean

3 0

3 years ago

Paige invested 1200 at an interest rate of 5.75% compounded quarterly. Determine the value of her investments in 7 years.

iragen [17]

Use the formula A=p(1+r)^n
where
A= value of investment
r= rate
n= time period
p= amount invested
in this question
r= 5.75% but compounded quarterly means divide this by 4
r= 23/1600
n=7*4
n=28
p= $1200
A=1200(1+23/1600)^28

A= $1789.54

Therefore the value of her investment in 7 years is $1789.54

4 0

3 years ago

What is the slope of the line passing through the points ( −3 , 4 ) and ( 4, −1 )?

ziro4ka [17]

Slope = (y2 - y1)/(x2 - x1) = (-1 - 4)/(4 - (-3)) = -5/(4 + 3) = -5/7

4 0

3 years ago