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2 years ago

Which set of ordered pairs does not represent a function?

Mathematics

1 answer:

Irina18 [472]2 years ago

3 0

<h3>Answer:</h3>

B. { (3, –2), (3, –4), (4, –1), (4, –3) }

<h3>Step-by-step explanation:</h3>

Functions are a set of points that show how dependent variables change through independent variables.

Defining a Function

In functions, each x-value is assigned to exactly one y-value. This means that x-values do not repeat. So, if there is one x-value more than once in a set, then it cannot be a function.

For example, set B has the x-value 3 and 4 repeated twice. Thus, it does not represent a function.

Graph of a Function

Functions can also be defined through a graph. Just like with coordinate points, x-values do not repeat on the graph. You can use the vertical line test to see if a graph is a function. If you can draw a vertical line at every point on a graph without it ever intersecting with the graph more than once, then it is a function.

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Tell whether you can make a unique triangle or no triangle with these conditions: angles measuring 45° and 90°

just olya [345]

Answer:

The triangle with those measures will be unique.

Step-by-step explanation:

The triangle described is an isosceles right triangle with side lengths 10 cm. All such triangles are congruent (it is unique).

7 0

3 years ago

A study of long-distance phone calls made from General Electric's corporate headquarters in Fairfield, Connecticut, revealed the

Jet001 [13]

Answer:

a) 0.4332 = 43.32% of the calls last between 3.6 and 4.2 minutes

b) 0.0668 = 6.68% of the calls last more than 4.2 minutes

c) 0.0666 = 6.66% of the calls last between 4.2 and 5 minutes

d) 0.9330 = 93.30% of the calls last between 3 and 5 minutes

e) They last at least 4.3 minutes

Step-by-step explanation:

Problems of normally distributed samples are solved using 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.

In this problem, we have that:

$\mu = 3.6, \sigma = 0.4$

(a) What fraction of the calls last between 3.6 and 4.2 minutes?

This is the pvalue of Z when X = 4.2 subtracted by the pvalue of Z when X = 3.6.

X = 4.2

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

$Z = \frac{4.2 - 3.6}{0.4}$

$Z = 1.5$

$Z = 1.5$ has a pvalue of 0.9332

X = 3.6

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

$Z = \frac{3.6 - 3.6}{0.4}$

$Z = 0$

$Z = 0$ has a pvalue of 0.5

0.9332 - 0.5 = 0.4332

0.4332 = 43.32% of the calls last between 3.6 and 4.2 minutes

(b) What fraction of the calls last more than 4.2 minutes?

This is 1 subtracted by the pvalue of Z when X = 4.2. So

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

$Z = \frac{4.2 - 3.6}{0.4}$

$Z = 1.5$

$Z = 1.5$ has a pvalue of 0.9332

1 - 0.9332 = 0.0668

0.0668 = 6.68% of the calls last more than 4.2 minutes

(c) What fraction of the calls last between 4.2 and 5 minutes?

This is the pvalue of Z when X = 5 subtracted by the pvalue of Z when X = 4.2. So

X = 5

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

$Z = \frac{5 - 3.6}{0.4}$

$Z = 3.5$

$Z = 3.5$ has a pvalue of 0.9998

X = 4.2

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

$Z = \frac{4.2 - 3.6}{0.4}$

$Z = 1.5$

$Z = 1.5$ has a pvalue of 0.9332

0.9998 - 0.9332 = 0.0666

0.0666 = 6.66% of the calls last between 4.2 and 5 minutes

(d) What fraction of the calls last between 3 and 5 minutes?

This is the pvalue of Z when X = 5 subtracted by the pvalue of Z when X = 3.

X = 5

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

$Z = \frac{5 - 3.6}{0.4}$

$Z = 3.5$

$Z = 3.5$ has a pvalue of 0.9998

X = 3

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

$Z = \frac{3 - 3.6}{0.4}$

$Z = -1.5$

$Z = -1.5$ has a pvalue of 0.0668

0.9998 - 0.0668 = 0.9330

0.9330 = 93.30% of the calls last between 3 and 5 minutes

(e) As part of her report to the president, the director of communications would like to report the length of the longest (in duration) 4% of the calls. What is this time?

At least X minutes

X is the 100-4 = 96th percentile, which is found when Z has a pvalue of 0.96. So X when Z = 1.75.

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

$1.75 = \frac{X - 3.6}{0.4}$

$X - 3.6 = 0.4*1.75$

$X = 4.3$

They last at least 4.3 minutes

7 0

3 years ago

Natalie and phil are running for 6th grade class president. Natalie receives 16 votes, and phil receives 12 votes.

sleet_krkn [62]

Natalie because Natalie has more votes

5 0

3 years ago

Read 2 more answers

It is known that the length of time that people wait for a city bus to arrive is right skewed with mean 6 minutes and standard d

Natali [406]

Answer:

The standard deviation of the sampling distribution of the sample wait times is of 0.8 minutes.

Step-by-step explanation:

Central Limit Theorem

The Central Limit Theorem establishes 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. Otherwise, the mean and the standard deviations holds, but the distribution will not be approximately normal.

Standard deviation 4 minutes.

This means that $\sigma = 4$

A sample of 25 wait times is randomly selected.

This means that $n = 25$

What is the standard deviation of the sampling distribution of the sample wait times?

$s = \frac{4}{\sqrt{25}} = 0.8$

The standard deviation of the sampling distribution of the sample wait times is of 0.8 minutes.

4 0

3 years ago

Andy’s goal for the week is to run 19 miles. he ran 6.19 miles between monday and friday. he ran 3.1 miles on saturday. how many

tatiyna

Answer:

9.71 miles

Step-by-step explanation:

total miles he ran = 6.19 + 3.1 = 9.29

Target = 19 miles

Goal for sunday = 19 - 9.29 = 9.71

5 0

3 years ago