Which of these constructions is impossible using only a compass and straightedge?

kenny6666 [7]

Hi! :) 19.7 - 6.8 is 12.9. If you need anymore help, ask me!

5 0

4 years ago

liza's friend marie bought her a dress for 250 euros in france. liza wants to pay marie for it in u.s. dollars. if the foreign e

Rudik [331]

1/ 0.6 = x / 250..1 dollar to 0.6 euros = x dollars to 250 euros
cross multiply
(0.6)(x) = (250)(1)
0.6x = 250
x = 250/0.6
x = 416.67 american dollars

8 0

4 years ago

Read 2 more answers

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