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2 years ago

Find the value of x in the figure below if RE is parallel to PM.

Mathematics

1 answer:

disa [49]2 years ago

8 0

Answer:

Option C. 7.2 units

Step-by-step explanation:

we know that

triangle PAM is similar to triangle RAE by AA Similarity Theorem

Remember that

If two triangles are similar, then the ratio of its corresponding sides is proportional and its corresponding angles are congruent

$\frac{PA}{RA}=\frac{AM}{AE}$

substitute the given values

$\frac{20+x}{20}=\frac{25+9}{25}$

solve for x

$\frac{20+x}{20}=\frac{34}{25}$

$20+x=\frac{34}{25}(20)$

$x=\frac{34}{25}(20)-20$

$x=7.2\ units$

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PLEASE ANSWER ITS DUE IN 5 MINUTES!! What is the are of the figure?

MariettaO [177]

Answer

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Step-by-step explanation:

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2 years ago

The life of light bulbs is distributed normally. the standard deviation of the lifetime is 25 hours and the mean lifetime of a b

Dominik [7]

The probability is 0.8997.

We will use a z-score to answer this question. z-scores are given by the formula
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With our information, we have
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2 years ago

To estimate the mean height μ of male students on your campus,you will measure an SRS of students. You know from government data

nexus9112 [7]

Answer:

a) $\sigma = 0.167$

b) We need a sample of at least 282 young men.

Step-by-step explanation:

Problems of normally distributed samples can be 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

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

This Zscore is how many standard deviations the value of the measure X 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.

(a) What standard deviation must x have so that 99.7% of allsamples give an x within one-half inch of μ?

To solve this problem, we use the 68-95-99.7 rule. This rule states that:

68% of the measures are within 1 standard deviation of the mean.

95% of the measures are within 2 standard deviations of the mean.

99.7% of the measures are within 3 standard deviations of the mean.

In this problem, we want 99.7% of all samples give X within one-half inch of $\mu$ . So $X - \mu = 0.5$ must have $Z = 3$ and $X - \mu = -0.5$ must have $Z = -3$ .

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

$3 = \frac{0.5}{\sigma}$

$3\sigma = 0.5$

$\sigma = \frac{0.5}{3}$

$\sigma = 0.167$

(b) How large an SRS do you need to reduce the standard deviationof x to the value you found in part (a)?

You know from government data that heights of young men are approximately Normal with standard deviation about 2.8 inches. This means that $\sigma = 2.8$