6X-1/5 = 3/1 please help fast first one gets brainlyest

Which of the following is a solution to 2cos x + 1 = 0? 60° 120° 210° 300°

klasskru [66]

Rewrite 2cos x + 1 = 0 as:

2 cos x = -1, and then cos x = -1/2

x must be in Quadrant II or Quadrant III, since the adj. side is negative.

Note that the angle 120 has adj. side -1 and hyp 2. So 120 degrees is one solution.

Now what about a possible 2nd solution, to be found in Quadrant III? That would be -120 degrees, which has the same terminal line as does 240 degrees.

No soap.

So, the solution is 120 degrees.

6 0

3 years ago

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Last week, Hazel paid $32 to have 50 reports printed. This week, she paid $57 to have 100 reports printed. Assume the relationsh

GenaCL600 [577]

The answer is the second one. Y=1/2x+7

6 0

4 years ago

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The children at Lincoln School go outside for recess if the temperature is 3°C or higher for what temperature will the students

Svetlanka [38]

Answer:

it has to be 37.4 degrees or higher. An inequality would be X≥37.4

step-by-step explanation:

4 0

3 years ago

Concerns about climate change and CO2 reduction have initiated the commercial production of blends of biodiesel (e.g., from rene

Veronika [31]

Answer:

99% of the sample means will fall between 0.93288 and 0.94112.

Step-by-step explanation:

To solve this question, we need to understand the normal probability distribution and the central limit theorem.

Normal Probability Distribution:

Problems of normal distributions can be solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the z-score 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 p-value, 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.

The true mean is .9370 with a standard deviation of 0.0090

This means that $\mu = 0.9370, \sigma = 0.0090$

Sample of 32:

This means that $n = 32, s = \frac{0.009}{32} = 0.0016$

Within what interval will 99 percent of the sample means fall?

Between the 50 - (99/2) = 0.5th percentile and the 50 + (99/2) = 99.5th percentile.

0.5th percentile:

X when Z has a pvalue of 0.005. So X when Z = -2.575.

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

By the Central Limit Theorem

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

$-2.575 = \frac{X - 0.9370}{0.0016}$

$X - 0.9370 = -2.575*0.0016$

$X = 0.93288$

99.5th percentile:

X when Z has a pvalue of 0.995. So X when Z = 2.575.

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

$2.575 = \frac{X - 0.9370}{0.0016}$

$X - 0.9370 = 2.575*0.0016$

$X = 0.94112$

99% of the sample means will fall between 0.93288 and 0.94112.

6 0

3 years ago

An owner of a small store knows that in the last week 54 customers paid with cash, 42 paid with a debit card, and 153 paid with

djverab [1.8K]

You would add 54+42+153=249 to find the total amount of customers from the previous week. Then you would divide 54/249= 0.2168 to find the amount of customers that used cash to total customers. The closest fraction would be about 1/5.

6 0

3 years ago

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