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3 years ago

Log10 (x squared - 4x + 7) = 2

1 answer:

6 0

Log_(10)(x² - 4x + 7) = 2

Take the base 10 anti log of both sides.
x² - 4x + 7 = 10² = 100
x²- 4x - 93 = 0

Quadratic Formula
x = [4 ± √(4²-4(1)(-93))]/[2(1)] = [4 ± 2√97)]/2 = 2 ± √97

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Pls help if u can 6th grademath

omeli [17]

Answer:

n = 54

Step-by-step explanation:

$\frac{2}{12}=\frac{9}{n}\\$

Cross products,

2 * n = 9 *12

2n = 108

Divide both sides by 2

$n = \frac{108}{2}\\$

n = 54

4 0

3 years ago

According to USA Today, the average cost of a private university is $50,000 with a population standard deviation of $2,500. 100

Colt1911 [192]

Using the z-distribution, it is found that since the p-value is less than 0.05, there is evidence to support the claim that the average cost of private universities are decreasing.

<h3>What are the hypothesis tested?</h3>

At the null hypothesis, it is tested if the average cost is still of $50,000, that is:

$H_0: \mu = 50000$

At the alternative hypothesis, it is tested if the average cost is decreasing, that is:

$H_1: \mu < 50000$

<h3>What is the test statistic?</h3>

The test statistic is:

$z = \frac{\overline{x} - \mu}{\frac{\sigma}{\sqrt{n}}}$

In which:

$\overline{x}$ is the sample mean.

$\mu$ is the value tested at the null hypothesis.

$\sigma$ is the standard deviation of the population.

n is the sample size.

The parameters for this problem are:

$\overline{x} = 49450, \mu = 50000, \sigma = 2500, n = 100$

Hence:

$z = \frac{\overline{x} - \mu}{\frac{\sigma}{\sqrt{n}}}$

$z = \frac{49450 - 50000}{\frac{2500}{\sqrt{100}}}$

z = -2.2.

<h3>What is the p-value and the conclusion?</h3>

Using a z-distribution calculator, for a left-tailed test, as we are testing if the mean is less than a value, with z = -2.2, the p-value is of 0.0139.

Since the p-value is less than 0.05, there is evidence to support the claim that the average cost of private universities are decreasing.

More can be learned about the z-distribution at brainly.com/question/16313918

#SPJ1

8 0

2 years ago

Rewrite the equation by completing the square.<br> x^2+ 10x + 24 = 0

Zarrin [17]

The answer is X= -4 or x = -6

3 0

3 years ago

Eric throws a biased coin 10 times. He gets 3 tails. Sue throw the same coin 50 times. She gets 20 tails. Aadi is going to throw

iren2701 [21]

Answer:

(1) The correct option is (A).

(2) The probability that Aadi will get Tails is $\frac{2}{5}$ .

Step-by-step explanation:

It is provided that:

Eric throws a biased coin 10 times. He gets 3 tails.
Sue throw the same coin 50 times. She gets 20 tails.

The probability of tail in both cases is:

$P(\text{Tail})=\frac{3}{10}$
$P(\text{Tail})=\frac{20}{50}=\frac{2}{5}$

(1)

According to the Central limit theorem, if from an unknown population large samples of sizes n > 30, are selected and the sample proportion for each sample is computed then the sampling distribution of sample proportion follows a Normal distribution.

In this case we need to compute the proportion of tails.

Then according to the Central limit theorem, Sue's estimate is best because she throws it <em>n = </em>50 > 30 times.

Thus, the correct option is (A).

(2)

As explained in the first part that Sue's estimate is best for getting a tail, the probability that Aadi will get Tails when he tosses the coin once is:

$P(\text{Tail})=\frac{20}{50}=\frac{2}{5}$

Thus, the probability that Aadi will get Tails is $\frac{2}{5}$ .

7 0

4 years ago

Read 2 more answers

100 cm divided 10 = _____dm?

olya-2409 [2.1K]

Answer:

100/10=10

Step-by-step explanation:

6 0

3 years ago

Read 2 more answers