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2 years ago

13

Which question is statistical? A) How many cookies are in a dozen? B) How many teachers gave an exam on Friday? C) What is your

student identification number? D) How many students from each homeroom signed up for tutoring?

2 answers:

sergey [27]2 years ago

8 0

The answer is d, because you can make it into percent and make it into graphs

igor_vitrenko [27]2 years ago

4 0

Answer:

Step-by-step explanation:

the answer is D

You might be interested in

A movie theater is holding a contest for people who are in line before 10 p.m. The people who are within three places of the 99

pav-90 [236]

Answer:

|x-99|<3

Step-by-step explanation:

|x-99|<3

4 0

3 years ago

Write an inequality for the graph

natima [27]

The open circle means the inequality will be greater than or equal to (≥) or less than or equal to (≤).
A closed circle means the inequality will be greater than (>) or less than (<)

An arrow pointing right to increasingly positive values means the inequality is getting greater (> or ≥)
A narrowing pointing left to increasingly negative values means the inequality is getting lesser (< or ≤)

So for this graph with an open circle and rightward pointing arrow, “x” will be some number on the number line greater than the first point of -38:
x > -38

6 0

3 years ago

A population has a mean of 200 and a standard deviation of 50. Suppose a sample of size 100 is selected and x is used to estimat

zmey [24]

Answer:

a) 0.6426 = 64.26% probability that the sample mean will be within +/- 5 of the population mean.

b) 0.9544 = 95.44% probability that the sample mean will be within +/- 10 of the population mean.

Step-by-step explanation:

To solve this question, we need to understand 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.

In this question, we have that:

$\mu = 200, \sigma = 50, n = 100, s = \frac{50}{\sqrt{100}} = 5$

a. What is the probability that the sample mean will be within +/- 5 of the population mean (to 4 decimals)?

This is the pvalue of Z when X = 200 + 5 = 205 subtracted by the pvalue of Z when X = 200 - 5 = 195.

Due to the Central Limit Theorem, Z is:

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

X = 205

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

$Z = \frac{205 - 200}{5}$

$Z = 1$

$Z = 1$ has a pvalue of 0.8413.

X = 195

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

$Z = \frac{195 - 200}{5}$

$Z = -1$

$Z = -1$ has a pvalue of 0.1587.

0.8413 - 0.1587 = 0.6426

0.6426 = 64.26% probability that the sample mean will be within +/- 5 of the population mean.

b. What is the probability that the sample mean will be within +/- 10 of the population mean (to 4 decimals)?

This is the pvalue of Z when X = 210 subtracted by the pvalue of Z when X = 190.

X = 210

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

$Z = \frac{210 - 200}{5}$

$Z = 2$

$Z = 2$ has a pvalue of 0.9772.

X = 195

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

$Z = \frac{190 - 200}{5}$

$Z = -2$

$Z = -2$ has a pvalue of 0.0228.

0.9772 - 0.0228 = 0.9544

0.9544 = 95.44% probability that the sample mean will be within +/- 10 of the population mean.

7 0

3 years ago

WILL GIVE BRAINLIEST What are the like terms in the algebraic expression? Negative a squared b + 6 a b minus 8 + 5 a squared b m

Minchanka [31]

Answer: B

Negative a squared b and 5 a squared b

Step-by-step explanation:

Given that:

Negative a squared b + 6 a b minus 8 + 5 a squared b minus 6 a minus b. That is,

- a^2b + 6ab - 8 + 5a^b - 6a - b

Collecting the like term by rearranging the expression

5a^2b - a^2b + 6ab - 6a - b

The like terms in the expression above are

5a^2b - a^2b.

The correct option is B:

Negative a squared b and 5 a squared b or (-a^2b and 5a^b)

4 0

3 years ago

Read 2 more answers

Is the least number to be added to 5607 to get a perfect square. <br> pls add the steps.

daser333 [38]

Answer:

18

Step-by-step explanation:

70^2 = 4900 < 5607 < 6400 = 80^2

so sqrt(5607) is a two-digit number with tenth-digit 7

71^2 = 5041, 72^2 = 5184, 73^2 = 5329, 74^2 = 5476, 75^2 = 5625

so the smallest square bigger than 5607 is 75^2, which is 5625

so the number should ne 5625 - 5607 = 18

8 0

2 years ago